MCQ Problems on Rocket Propellants and Their Performance
Characteristics
1. If a solid propellant rocket has a specific impulse of 250 seconds and produces 10,000 N of thrust,
what is its propellant mass flow rate?
a) 3.08 kg/s
b) 4.08 kg/s
c) 5.08 kg/s
d) 6.08 kg/s
Answer: b) 4.08 kg/s
2. A liquid propellant rocket engine has a thrust of 500,000 N and an exhaust velocity of 3000 m/s.
What is its specific impulse?
a) 285.9 seconds
b) 295.9 seconds
c) 305.9 seconds
d) 315.9 seconds
Answer: c) 305.9 seconds
3. If a hybrid rocket motor uses 100 kg of propellant in 30 seconds, what is its average propellant
consumption rate?
a) 2.33 kg/s
b) 3.33 kg/s
c) 4.33 kg/s
d) 5.33 kg/s
Answer: b) 3.33 kg/s
4. A solid rocket booster has a burn time of 120 seconds and contains 50,000 kg of propellant. What
is its average propellant mass flow rate?
a) 316.67 kg/s
b) 366.67 kg/s
c) 416.67 kg/s
d) 466.67 kg/s
Answer: c) 416.67 kg/s
5. If a liquid propellant rocket has a mixture ratio (oxidizer to fuel) of 2.5:1 and uses 150 kg of
propellant, how much oxidizer is used?
a) 97.14 kg
b) 107.14 kg
c) 117.14 kg
d) 127.14 kg
Answer: b) 107.14 kg
6. A rocket engine has a chamber pressure of 7 MPa and an exit pressure of 100 kPa. What is its
pressure ratio?
a) 50
b) 60
c) 70
d) 80
Answer: c) 70
7. If a solid propellant has a density of 1800 kg/m³ and a rocket motor requires 500 kg of propellant,
what volume does the propellant occupy?
a) 0.178 m³
b) 0.228 m³
c) 0.278 m³
d) 0.328 m³
Answer: c) 0.278 m³
8. A liquid oxygen/kerosene rocket engine has a specific impulse of 300 seconds at sea level. What is
its exhaust velocity?
a) 2743 m/s
b) 2843 m/s
c) 2943 m/s
d) 3043 m/s
Answer: c) 2943 m/s
9. If a hybrid rocket motor has a regression rate of 2 mm/s and burns for 25 seconds, how much of
the solid fuel is consumed (in thickness)?
a) 40 mm
b) 45 mm
c) 50 mm
d) 55 mm
Answer: c) 50 mm
10. A solid rocket motor has a propellant mass of 1000 kg and produces 250 kN of thrust for 40
seconds. What is its specific impulse?
a) 220 seconds
b) 240 seconds
c) 260 seconds
d) 280 seconds
Answer: b) 240 seconds
11. If a liquid propellant rocket engine has a thrust of 100 kN and a specific impulse of 310 seconds,
what is its propellant mass flow rate?
a) 32.9 kg/s
b) 33.9 kg/s
c) 34.9 kg/s
d) 35.9 kg/s
Answer: a) 32.9 kg/s
12. A hybrid rocket uses 80% solid fuel and 20% liquid oxidizer by mass. If the total propellant mass is
500 kg, how much solid fuel is used?
a) 350 kg
b) 375 kg
c) 400 kg
d) 425 kg
Answer: c) 400 kg
13. If a solid propellant has a burning rate of 10 mm/s at a reference pressure of 7 MPa, and the
pressure exponent is 0.4, what is the burning rate at 10 MPa?
a) 11.5 mm/s
b) 12.0 mm/s
c) 12.5 mm/s
d) 13.0 mm/s
Answer: b) 12.0 mm/s
14. A liquid propellant rocket engine has a chamber temperature of 3500 K and a specific heat ratio
of 1.2. If the nozzle expansion ratio is 20, what is the thrust coefficient?
a) 1.59
b) 1.69
c) 1.79
d) 1.89
Answer: c) 1.79
15. If a solid rocket motor has a burn area of 2 m² and a propellant density of 1750 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 5 mm/s?
a) 15.5 kg/s
b) 16.5 kg/s
c) 17.5 kg/s
d) 18.5 kg/s
Answer: c) 17.5 kg/s
16. A liquid propellant rocket has a mixture ratio of 3:1 (oxidizer to fuel). If it consumes 80 kg of fuel
per second, what is the total propellant flow rate?
a) 300 kg/s
b) 310 kg/s
c) 320 kg/s
d) 330 kg/s
Answer: c) 320 kg/s
17. If a hybrid rocket motor has a fuel grain with an initial port diameter of 50 mm and a final port
diameter of 150 mm after burning, what is the average regression rate if the burn time is 30
seconds?
a) 1.33 mm/s
b) 1.67 mm/s
c) 2.00 mm/s
d) 2.33 mm/s
Answer: b) 1.67 mm/s
18. A solid propellant rocket has a propellant mass fraction of 0.85 and a total mass of 10,000 kg.
How much propellant does it contain?
a) 7500 kg
b) 8000 kg
c) 8500 kg
d) 9000 kg
Answer: c) 8500 kg
19. If a liquid propellant rocket engine has a chamber pressure of 5 MPa and a throat area of 0.1 m²,
what is the mass flow rate if the characteristic velocity is 1500 m/s?
a) 323 kg/s
b) 333 kg/s
c) 343 kg/s
d) 353 kg/s
Answer: b) 333 kg/s
20. A hybrid rocket motor uses 70% of its oxidizer in the first 20 seconds of a 50-second burn. If the
total oxidizer mass is 1000 kg, what is the average oxidizer flow rate for the last 30 seconds?
a) 8 kg/s
b) 9 kg/s
c) 10 kg/s
d) 11 kg/s
Answer: c) 10 kg/s
21. If a solid propellant has a density of 1800 kg/m³ and a specific heat of 1500 J/(kg·K), what is its
volumetric heat capacity?
a) 2.5 MJ/(m³·K)
b) 2.7 MJ/(m³·K)
c) 2.9 MJ/(m³·K)
d) 3.1 MJ/(m³·K)
Answer: b) 2.7 MJ/(m³·K)
22. A liquid propellant rocket engine has a thrust of 200 kN and a specific impulse of 320 seconds.
What is its propellant consumption rate?
a) 61.3 kg/s
b) 63.3 kg/s
c) 65.3 kg/s
d) 67.3 kg/s
Answer: b) 63.3 kg/s
23. If a hybrid rocket motor has a regression rate coefficient of 0.5 mm/(s·MPa^0.5) and operates at a
chamber pressure of 4 MPa, what is its regression rate?
a) 0.8 mm/s
b) 1.0 mm/s
c) 1.2 mm/s
d) 1.4 mm/s
Answer: b) 1.0 mm/s
24. A solid rocket booster produces 1.5 MN of thrust for 120 seconds. If its specific impulse is 250
seconds, how much propellant does it consume?
a) 7200 kg
b) 7400 kg
c) 7600 kg
d) 7800 kg
Answer: a) 7200 kg
25. If a liquid propellant rocket has a mixture ratio of 2.2:1 and uses 330 kg of propellant, how much
fuel is used?
a) 101.3 kg
b) 103.1 kg
c) 105.9 kg
d) 107.7 kg
Answer: b) 103.1 kg
26. A rocket engine has a chamber pressure of 10 MPa and an exit pressure of 50 kPa. What is its
pressure ratio?
a) 180
b) 190
c) 200
d) 210
Answer: c) 200
27. If a solid propellant has a density of 1700 kg/m³ and a rocket motor requires 800 kg of propellant,
what volume does the propellant occupy?
a) 0.451 m³
b) 0.461 m³
c) 0.471 m³
d) 0.481 m³
Answer: c) 0.471 m³
28. A liquid hydrogen/liquid oxygen rocket engine has a specific impulse of 450 seconds in vacuum.
What is its exhaust velocity?
a) 4313 m/s
b) 4413 m/s
c) 4513 m/s
d) 4613 m/s
Answer: b) 4413 m/s
29. If a hybrid rocket motor has a regression rate of 1.5 mm/s and burns for 40 seconds, how much of
the solid fuel is consumed (in thickness)?
a) 50 mm
b) 55 mm
c) 60 mm
d) 65 mm
Answer: c) 60 mm
30. A solid rocket motor has a propellant mass of 2000 kg and produces 400 kN of thrust for 30
seconds. What is its specific impulse?
a) 180 seconds
b) 190 seconds
c) 200 seconds
d) 210 seconds
Answer: c) 200 seconds
31. If a liquid propellant rocket engine has a thrust of 150 kN and a specific impulse of 330 seconds,
what is its propellant mass flow rate?
a) 45.5 kg/s
b) 46.5 kg/s
c) 47.5 kg/s
d) 48.5 kg/s
Answer: b) 46.5 kg/s
32. A hybrid rocket uses 75% solid fuel and 25% liquid oxidizer by mass. If the total propellant mass is
600 kg, how much liquid oxidizer is used?
a) 125 kg
b) 135 kg
c) 145 kg
d) 150 kg
Answer: d) 150 kg
33. If a solid propellant has a burning rate of 8 mm/s at a reference pressure of 5 MPa, and the
pressure exponent is 0.3, what is the burning rate at 8 MPa?
a) 9.1 mm/s
b) 9.3 mm/s
c) 9.5 mm/s
d) 9.7 mm/s
Answer: c) 9.5 mm/s
34. A liquid propellant rocket engine has a chamber temperature of 3200 K and a specific heat ratio
of 1.25. If the nozzle expansion ratio is 25, what is the thrust coefficient?
a) 1.75
b) 1.80
c) 1.85
d) 1.90
Answer: b) 1.80
35. If a solid rocket motor has a burn area of 1.5 m² and a propellant density of 1800 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 6 mm/s?
a) 15.5 kg/s
b) 16.2 kg/s
c) 16.9 kg/s
d) 17.6 kg/s
Answer: b) 16.2 kg/s
36. A liquid propellant rocket has a mixture ratio of 2.5:1 (oxidizer to fuel). If it consumes 100 kg of
fuel per second, what is the total propellant flow rate?
a) 330 kg/s
b) 340 kg/s
c) 350 kg/s
d) 360 kg/s
Answer: c) 350 kg/s
37. If a hybrid rocket motor has a fuel grain with an initial port diameter of 40 mm and a final port
diameter of 120 mm after burning, what is the average regression rate if the burn time is 25
seconds?
a) 1.4 mm/s
b) 1.6 mm/s
c) 1.8 mm/s
d) 2.0 mm/s
Answer: b) 1.6 mm/s
38. A solid propellant rocket has a propellant mass fraction of 0.88 and a total mass of 12,000 kg.
How much propellant does it contain?
a) 10,320 kg
b) 10,440 kg
c) 10,560 kg
d) 10,680 kg
Answer: c) 10,560 kg
39. If a liquid propellant rocket engine has a chamber pressure of 6 MPa and a throat area of 0.08 m²,
what is the mass flow rate if the characteristic velocity is 1600 m/s?
a) 290 kg/s
b) 300 kg/s
c) 310 kg/s
d) 320 kg/s
Answer: b) 300 kg/s
40. A hybrid rocket motor uses 60% of its oxidizer in the first 15 seconds of a 40-second burn. If the
total oxidizer mass is 800 kg, what is the average oxidizer flow rate for the last 25 seconds?
a) 11.2 kg/s
b) 12.2 kg/s
c) 12.8 kg/s
d) 13.2 kg/s
Answer: c) 12.8 kg/s
41. If a solid propellant has a density of 1750 kg/m³ and a specific heat of 1400 J/(kg·K), what is its
volumetric heat capacity?
a) 2.35 MJ/(m³·K)
b) 2.45 MJ/(m³·K)
c) 2.55 MJ/(m³·K)
d) 2.65 MJ/(m³·K)
Answer: b) 2.45 MJ/(m³·K)
42. A liquid propellant rocket engine has a thrust of 250 kN and a specific impulse of 340 seconds.
What is its propellant consumption rate?
a) 73.5 kg/s
b) 74.5 kg/s
c) 75.5 kg/s
d) 76.5 kg/s
Answer: c) 75.5 kg/s
A solid rocket motor has a propellant mass of 1000 kg and produces 250 kN of thrust for 40 seconds.
What is its specific impulse?
a) 220 seconds
b) 240 seconds
c) 260 seconds
d) 280 seconds
Answer: b) 240 seconds
11. If a liquid propellant rocket engine has a thrust of 100 kN and a specific impulse of 310 seconds,
what is its propellant mass flow rate?
a) 32.9 kg/s
b) 33.9 kg/s
c) 34.9 kg/s
d) 35.9 kg/s
Answer: a) 32.9 kg/s
12. A hybrid rocket uses 80% solid fuel and 20% liquid oxidizer by mass. If the total propellant mass is
500 kg, how much solid fuel is used?
a) 350 kg
b) 375 kg
c) 400 kg
d) 425 kg
Answer: c) 400 kg
13. If a solid propellant has a burning rate of 10 mm/s at a reference pressure of 7 MPa, and the
pressure exponent is 0.4, what is the burning rate at 10 MPa?
a) 11.5 mm/s
b) 12.0 mm/s
c) 12.5 mm/s
d) 13.0 mm/s
Answer: b) 12.0 mm/s
14. A liquid propellant rocket engine has a chamber temperature of 3500 K and a specific heat ratio
of 1.2. If the nozzle expansion ratio is 20, what is the thrust coefficient?
a) 1.59
b) 1.69
c) 1.79
d) 1.89
Answer: c) 1.79
15. If a solid rocket motor has a burn area of 2 m² and a propellant density of 1750 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 5 mm/s?
a) 15.5 kg/s
b) 16.5 kg/s
c) 17.5 kg/s
d) 18.5 kg/s
Answer: c) 17.5 kg/s
16. A liquid propellant rocket has a mixture ratio of 3:1 (oxidizer to fuel). If it consumes 80 kg of fuel
per second, what is the total propellant flow rate?
a) 300 kg/s
b) 310 kg/s
c) 320 kg/s
d) 330 kg/s
Answer: c) 320 kg/s
17. If a hybrid rocket motor has a fuel grain with an initial port diameter of 50 mm and a final port
diameter of 150 mm after burning, what is the average regression rate if the burn time is 30
seconds?
a) 1.33 mm/s
b) 1.67 mm/s
c) 2.00 mm/s
d) 2.33 mm/s
Answer: b) 1.67 mm/s
18. A solid propellant rocket has a propellant mass fraction of 0.85 and a total mass of 10,000 kg.
How much propellant does it contain?
a) 7500 kg
b) 8000 kg
c) 8500 kg
d) 9000 kg
Answer: c) 8500 kg
19. If a liquid propellant rocket engine has a chamber pressure of 5 MPa and a throat area of 0.1 m²,
what is the mass flow rate if the characteristic velocity is 1500 m/s?
a) 323 kg/s
b) 333 kg/s
c) 343 kg/s
d) 353 kg/s
Answer: b) 333 kg/s
20. A hybrid rocket motor uses 70% of its oxidizer in the first 20 seconds of a 50-second burn. If the
total oxidizer mass is 1000 kg, what is the average oxidizer flow rate for the last 30 seconds?
a) 8 kg/s
b) 9 kg/s
c) 10 kg/s
d) 11 kg/s
Answer: c) 10 kg/s
21. If a solid propellant has a density of 1800 kg/m³ and a specific heat of 1500 J/(kg·K), what is its
volumetric heat capacity?
a) 2.5 MJ/(m³·K)
b) 2.7 MJ/(m³·K)
c) 2.9 MJ/(m³·K)
d) 3.1 MJ/(m³·K)
Answer: b) 2.7 MJ/(m³·K)
22. A liquid propellant rocket engine has a thrust of 200 kN and a specific impulse of 320 seconds.
What is its propellant consumption rate?
a) 61.3 kg/s
b) 63.3 kg/s
c) 65.3 kg/s
d) 67.3 kg/s
Answer: b) 63.3 kg/s
23. If a hybrid rocket motor has a regression rate coefficient of 0.5 mm/(s·MPa^0.5) and operates at a
chamber pressure of 4 MPa, what is its regression rate?
a) 0.8 mm/s
b) 1.0 mm/s
c) 1.2 mm/s
d) 1.4 mm/s
Answer: b) 1.0 mm/s
24. A solid rocket booster produces 1.5 MN of thrust for 120 seconds. If its specific impulse is 250
seconds, how much propellant does it consume?
a) 7200 kg
b) 7400 kg
c) 7600 kg
d) 7800 kg
Answer: a) 7200 kg
25. If a liquid propellant rocket has a mixture ratio of 2.2:1 and uses 330 kg of propellant, how much
fuel is used?
a) 101.3 kg
b) 103.1 kg
c) 105.9 kg
d) 107.7 kg
Answer: b) 103.1 kg
26. A rocket engine has a chamber pressure of 10 MPa and an exit pressure of 50 kPa. What is its
pressure ratio?
a) 180
b) 190
c) 200
d) 210
Answer: c) 200
27. If a solid propellant has a density of 1700 kg/m³ and a rocket motor requires 800 kg of propellant,
what volume does the propellant occupy?
a) 0.451 m³
b) 0.461 m³
c) 0.471 m³
d) 0.481 m³
Answer: c) 0.471 m³
28. A liquid hydrogen/liquid oxygen rocket engine has a specific impulse of 450 seconds in vacuum.
What is its exhaust velocity?
a) 4313 m/s
b) 4413 m/s
c) 4513 m/s
d) 4613 m/s
Answer: b) 4413 m/s
29. If a hybrid rocket motor has a regression rate of 1.5 mm/s and burns for 40 seconds, how much of
the solid fuel is consumed (in thickness)?
a) 50 mm
b) 55 mm
c) 60 mm
d) 65 mm
Answer: c) 60 mm
30. A solid rocket motor has a propellant mass of 2000 kg and produces 400 kN of thrust for 30
seconds. What is its specific impulse?
a) 180 seconds
b) 190 seconds
c) 200 seconds
d) 210 seconds
Answer: c) 200 seconds
31. If a liquid propellant rocket engine has a thrust of 150 kN and a specific impulse of 330 seconds,
what is its propellant mass flow rate?
a) 45.5 kg/s
b) 46.5 kg/s
c) 47.5 kg/s
d) 48.5 kg/s
Answer: b) 46.5 kg/s
32. A hybrid rocket uses 75% solid fuel and 25% liquid oxidizer by mass. If the total propellant mass is
600 kg, how much liquid oxidizer is used?
a) 125 kg
b) 135 kg
c) 145 kg
d) 150 kg
Answer: d) 150 kg
33. If a solid propellant has a burning rate of 8 mm/s at a reference pressure of 5 MPa, and the
pressure exponent is 0.3, what is the burning rate at 8 MPa?
a) 9.1 mm/s
b) 9.3 mm/s
c) 9.5 mm/s
d) 9.7 mm/s
Answer: c) 9.5 mm/s
34. A liquid propellant rocket engine has a chamber temperature of 3200 K and a specific heat ratio
of 1.25. If the nozzle expansion ratio is 25, what is the thrust coefficient?
a) 1.75
b) 1.80
c) 1.85
d) 1.90
Answer: b) 1.80
35. If a solid rocket motor has a burn area of 1.5 m² and a propellant density of 1800 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 6 mm/s?
a) 15.5 kg/s
b) 16.2 kg/s
c) 16.9 kg/s
d) 17.6 kg/s
Answer: b) 16.2 kg/s
36. A liquid propellant rocket has a mixture ratio of 2.5:1 (oxidizer to fuel). If it consumes 100 kg of
fuel per second, what is the total propellant flow rate?
a) 330 kg/s
b) 340 kg/s
c) 350 kg/s
d) 360 kg/s
Answer: c) 350 kg/s
37. If a hybrid rocket motor has a fuel grain with an initial port diameter of 40 mm and a final port
diameter of 120 mm after burning, what is the average regression rate if the burn time is 25
seconds?
a) 1.4 mm/s
b) 1.6 mm/s
c) 1.8 mm/s
d) 2.0 mm/s
Answer: b) 1.6 mm/s
38. A solid propellant rocket has a propellant mass fraction of 0.88 and a total mass of 12,000 kg.
How much propellant does it contain?
a) 10,320 kg
b) 10,440 kg
c) 10,560 kg
d) 10,680 kg
Answer: c) 10,560 kg
39. If a liquid propellant rocket engine has a chamber pressure of 6 MPa and a throat area of 0.08 m²,
what is the mass flow rate if the characteristic velocity is 1600 m/s?
a) 290 kg/s
b) 300 kg/s
c) 310 kg/s
d) 320 kg/s
Answer: b) 300 kg/s
40. A hybrid rocket motor uses 60% of its oxidizer in the first 15 seconds of a 40-second burn. If the
total oxidizer mass is 800 kg, what is the average oxidizer flow rate for the last 25 seconds?
a) 11.2 kg/s
b) 12.2 kg/s
c) 12.8 kg/s
d) 13.2 kg/s
Answer: c) 12.8 kg/s
41. If a solid propellant has a density of 1750 kg/m³ and a specific heat of 1400 J/(kg·K), what is its
volumetric heat capacity?
a) 2.35 MJ/(m³·K)
b) 2.45 MJ/(m³·K)
c) 2.55 MJ/(m³·K)
d) 2.65 MJ/(m³·K)
Answer: b) 2.45 MJ/(m³·K)
42. A liquid propellant rocket engine has a thrust of 250 kN and a specific impulse of 340 seconds.
What is its propellant consumption rate?
a) 73.5 kg/s
b) 74.5 kg/s
c) 75.5 kg/s
d) 76.5 kg/s
Answer: c) 75.5 kg/s
A solid rocket motor has a propellant mass of 1000 kg and produces 250 kN of thrust for 40 seconds.
What is its specific impulse?
a) 220 seconds
b) 240 seconds
c) 260 seconds
d) 280 seconds
Answer: b) 240 seconds
11. If a liquid propellant rocket engine has a thrust of 100 kN and a specific impulse of 310 seconds,
what is its propellant mass flow rate?
a) 32.9 kg/s
b) 33.9 kg/s
c) 34.9 kg/s
d) 35.9 kg/s
Answer: a) 32.9 kg/s
12. A hybrid rocket uses 80% solid fuel and 20% liquid oxidizer by mass. If the total propellant mass is
500 kg, how much solid fuel is used?
a) 350 kg
b) 375 kg
c) 400 kg
d) 425 kg
Answer: c) 400 kg
13. If a solid propellant has a burning rate of 10 mm/s at a reference pressure of 7 MPa, and the
pressure exponent is 0.4, what is the burning rate at 10 MPa?
a) 11.5 mm/s
b) 12.0 mm/s
c) 12.5 mm/s
d) 13.0 mm/s
Answer: b) 12.0 mm/s
14. A liquid propellant rocket engine has a chamber temperature of 3500 K and a specific heat ratio
of 1.2. If the nozzle expansion ratio is 20, what is the thrust coefficient?
a) 1.59
b) 1.69
c) 1.79
d) 1.89
Answer: c) 1.79
15. If a solid rocket motor has a burn area of 2 m² and a propellant density of 1750 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 5 mm/s?
a) 15.5 kg/s
b) 16.5 kg/s
c) 17.5 kg/s
d) 18.5 kg/s
Answer: c) 17.5 kg/s
16. A liquid propellant rocket has a mixture ratio of 3:1 (oxidizer to fuel). If it consumes 80 kg of fuel
per second, what is the total propellant flow rate?
a) 300 kg/s
b) 310 kg/s
c) 320 kg/s
d) 330 kg/s
Answer: c) 320 kg/s
17. If a hybrid rocket motor has a fuel grain with an initial port diameter of 50 mm and a final port
diameter of 150 mm after burning, what is the average regression rate if the burn time is 30
seconds?
a) 1.33 mm/s
b) 1.67 mm/s
c) 2.00 mm/s
d) 2.33 mm/s
Answer: b) 1.67 mm/s
18. A solid propellant rocket has a propellant mass fraction of 0.85 and a total mass of 10,000 kg.
How much propellant does it contain?
a) 7500 kg
b) 8000 kg
c) 8500 kg
d) 9000 kg
Answer: c) 8500 kg
19. If a liquid propellant rocket engine has a chamber pressure of 5 MPa and a throat area of 0.1 m²,
what is the mass flow rate if the characteristic velocity is 1500 m/s?
a) 323 kg/s
b) 333 kg/s
c) 343 kg/s
d) 353 kg/s
Answer: b) 333 kg/s
20. A hybrid rocket motor uses 70% of its oxidizer in the first 20 seconds of a 50-second burn. If the
total oxidizer mass is 1000 kg, what is the average oxidizer flow rate for the last 30 seconds?
a) 8 kg/s
b) 9 kg/s
c) 10 kg/s
d) 11 kg/s
Answer: c) 10 kg/s
21. If a solid propellant has a density of 1800 kg/m³ and a specific heat of 1500 J/(kg·K), what is its
volumetric heat capacity?
a) 2.5 MJ/(m³·K)
b) 2.7 MJ/(m³·K)
c) 2.9 MJ/(m³·K)
d) 3.1 MJ/(m³·K)
Answer: b) 2.7 MJ/(m³·K)
22. A liquid propellant rocket engine has a thrust of 200 kN and a specific impulse of 320 seconds.
What is its propellant consumption rate?
a) 61.3 kg/s
b) 63.3 kg/s
c) 65.3 kg/s
d) 67.3 kg/s
Answer: b) 63.3 kg/s
23. If a hybrid rocket motor has a regression rate coefficient of 0.5 mm/(s·MPa^0.5) and operates at a
chamber pressure of 4 MPa, what is its regression rate?
a) 0.8 mm/s
b) 1.0 mm/s
c) 1.2 mm/s
d) 1.4 mm/s
Answer: b) 1.0 mm/s
24. A solid rocket booster produces 1.5 MN of thrust for 120 seconds. If its specific impulse is 250
seconds, how much propellant does it consume?
a) 7200 kg
b) 7400 kg
c) 7600 kg
d) 7800 kg
Answer: a) 7200 kg
25. If a liquid propellant rocket has a mixture ratio of 2.2:1 and uses 330 kg of propellant, how much
fuel is used?
a) 101.3 kg
b) 103.1 kg
c) 105.9 kg
d) 107.7 kg
Answer: b) 103.1 kg
26. A rocket engine has a chamber pressure of 10 MPa and an exit pressure of 50 kPa. What is its
pressure ratio?
a) 180
b) 190
c) 200
d) 210
Answer: c) 200
27. If a solid propellant has a density of 1700 kg/m³ and a rocket motor requires 800 kg of propellant,
what volume does the propellant occupy?
a) 0.451 m³
b) 0.461 m³
c) 0.471 m³
d) 0.481 m³
Answer: c) 0.471 m³
28. A liquid hydrogen/liquid oxygen rocket engine has a specific impulse of 450 seconds in vacuum.
What is its exhaust velocity?
a) 4313 m/s
b) 4413 m/s
c) 4513 m/s
d) 4613 m/s
Answer: b) 4413 m/s
29. If a hybrid rocket motor has a regression rate of 1.5 mm/s and burns for 40 seconds, how much of
the solid fuel is consumed (in thickness)?
a) 50 mm
b) 55 mm
c) 60 mm
d) 65 mm
Answer: c) 60 mm
30. A solid rocket motor has a propellant mass of 2000 kg and produces 400 kN of thrust for 30
seconds. What is its specific impulse?
a) 180 seconds
b) 190 seconds
c) 200 seconds
d) 210 seconds
Answer: c) 200 seconds
31. If a liquid propellant rocket engine has a thrust of 150 kN and a specific impulse of 330 seconds,
what is its propellant mass flow rate?
a) 45.5 kg/s
b) 46.5 kg/s
c) 47.5 kg/s
d) 48.5 kg/s
Answer: b) 46.5 kg/s
32. A hybrid rocket uses 75% solid fuel and 25% liquid oxidizer by mass. If the total propellant mass is
600 kg, how much liquid oxidizer is used?
a) 125 kg
b) 135 kg
c) 145 kg
d) 150 kg
Answer: d) 150 kg
33. If a solid propellant has a burning rate of 8 mm/s at a reference pressure of 5 MPa, and the
pressure exponent is 0.3, what is the burning rate at 8 MPa?
a) 9.1 mm/s
b) 9.3 mm/s
c) 9.5 mm/s
d) 9.7 mm/s
Answer: c) 9.5 mm/s
34. A liquid propellant rocket engine has a chamber temperature of 3200 K and a specific heat ratio
of 1.25. If the nozzle expansion ratio is 25, what is the thrust coefficient?
a) 1.75
b) 1.80
c) 1.85
d) 1.90
Answer: b) 1.80
35. If a solid rocket motor has a burn area of 1.5 m² and a propellant density of 1800 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 6 mm/s?
a) 15.5 kg/s
b) 16.2 kg/s
c) 16.9 kg/s
d) 17.6 kg/s
Answer: b) 16.2 kg/s
36. A liquid propellant rocket has a mixture ratio of 2.5:1 (oxidizer to fuel). If it consumes 100 kg of
fuel per second, what is the total propellant flow rate?
a) 330 kg/s
b) 340 kg/s
c) 350 kg/s
d) 360 kg/s
Answer: c) 350 kg/s
37. If a hybrid rocket motor has a fuel grain with an initial port diameter of 40 mm and a final port
diameter of 120 mm after burning, what is the average regression rate if the burn time is 25
seconds?
a) 1.4 mm/s
b) 1.6 mm/s
c) 1.8 mm/s
d) 2.0 mm/s
Answer: b) 1.6 mm/s
38. A solid propellant rocket has a propellant mass fraction of 0.88 and a total mass of 12,000 kg.
How much propellant does it contain?
a) 10,320 kg
b) 10,440 kg
c) 10,560 kg
d) 10,680 kg
Answer: c) 10,560 kg
39. If a liquid propellant rocket engine has a chamber pressure of 6 MPa and a throat area of 0.08 m²,
what is the mass flow rate if the characteristic velocity is 1600 m/s?
a) 290 kg/s
b) 300 kg/s
c) 310 kg/s
d) 320 kg/s
Answer: b) 300 kg/s
40. A hybrid rocket motor uses 60% of its oxidizer in the first 15 seconds of a 40-second burn. If the
total oxidizer mass is 800 kg, what is the average oxidizer flow rate for the last 25 seconds?
a) 11.2 kg/s
b) 12.2 kg/s
c) 12.8 kg/s
d) 13.2 kg/s
Answer: c) 12.8 kg/s
41. If a solid propellant has a density of 1750 kg/m³ and a specific heat of 1400 J/(kg·K), what is its
volumetric heat capacity?
a) 2.35 MJ/(m³·K)
b) 2.45 MJ/(m³·K)
c) 2.55 MJ/(m³·K)
d) 2.65 MJ/(m³·K)
Answer: b) 2.45 MJ/(m³·K)
42. A liquid propellant rocket engine has a thrust of 250 kN and a specific impulse of 340 seconds.
What is its propellant consumption rate?
a) 73.5 kg/s
b) 74.5 kg/s
c) 75.5 kg/s
d) 76.5 kg/s
Answer: c) 75.5 kg/s
A solid rocket motor has a propellant mass of 1000 kg and produces 250 kN of thrust for 40 seconds.
What is its specific impulse?
a) 220 seconds
b) 240 seconds
c) 260 seconds
d) 280 seconds
Answer: b) 240 seconds
11. If a liquid propellant rocket engine has a thrust of 100 kN and a specific impulse of 310 seconds,
what is its propellant mass flow rate?
a) 32.9 kg/s
b) 33.9 kg/s
c) 34.9 kg/s
d) 35.9 kg/s
Answer: a) 32.9 kg/s
12. A hybrid rocket uses 80% solid fuel and 20% liquid oxidizer by mass. If the total propellant mass is
500 kg, how much solid fuel is used?
a) 350 kg
b) 375 kg
c) 400 kg
d) 425 kg
Answer: c) 400 kg
13. If a solid propellant has a burning rate of 10 mm/s at a reference pressure of 7 MPa, and the
pressure exponent is 0.4, what is the burning rate at 10 MPa?
a) 11.5 mm/s
b) 12.0 mm/s
c) 12.5 mm/s
d) 13.0 mm/s
Answer: b) 12.0 mm/s
14. A liquid propellant rocket engine has a chamber temperature of 3500 K and a specific heat ratio
of 1.2. If the nozzle expansion ratio is 20, what is the thrust coefficient?
a) 1.59
b) 1.69
c) 1.79
d) 1.89
Answer: c) 1.79
15. If a solid rocket motor has a burn area of 2 m² and a propellant density of 1750 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 5 mm/s?
a) 15.5 kg/s
b) 16.5 kg/s
c) 17.5 kg/s
d) 18.5 kg/s
Answer: c) 17.5 kg/s
16. A liquid propellant rocket has a mixture ratio of 3:1 (oxidizer to fuel). If it consumes 80 kg of fuel
per second, what is the total propellant flow rate?
a) 300 kg/s
b) 310 kg/s
c) 320 kg/s
d) 330 kg/s
Answer: c) 320 kg/s
17. If a hybrid rocket motor has a fuel grain with an initial port diameter of 50 mm and a final port
diameter of 150 mm after burning, what is the average regression rate if the burn time is 30
seconds?
a) 1.33 mm/s
b) 1.67 mm/s
c) 2.00 mm/s
d) 2.33 mm/s
Answer: b) 1.67 mm/s
18. A solid propellant rocket has a propellant mass fraction of 0.85 and a total mass of 10,000 kg.
How much propellant does it contain?
a) 7500 kg
b) 8000 kg
c) 8500 kg
d) 9000 kg
Answer: c) 8500 kg
19. If a liquid propellant rocket engine has a chamber pressure of 5 MPa and a throat area of 0.1 m²,
what is the mass flow rate if the characteristic velocity is 1500 m/s?
a) 323 kg/s
b) 333 kg/s
c) 343 kg/s
d) 353 kg/s
Answer: b) 333 kg/s
20. A hybrid rocket motor uses 70% of its oxidizer in the first 20 seconds of a 50-second burn. If the
total oxidizer mass is 1000 kg, what is the average oxidizer flow rate for the last 30 seconds?
a) 8 kg/s
b) 9 kg/s
c) 10 kg/s
d) 11 kg/s
Answer: c) 10 kg/s
21. If a solid propellant has a density of 1800 kg/m³ and a specific heat of 1500 J/(kg·K), what is its
volumetric heat capacity?
a) 2.5 MJ/(m³·K)
b) 2.7 MJ/(m³·K)
c) 2.9 MJ/(m³·K)
d) 3.1 MJ/(m³·K)
Answer: b) 2.7 MJ/(m³·K)
22. A liquid propellant rocket engine has a thrust of 200 kN and a specific impulse of 320 seconds.
What is its propellant consumption rate?
a) 61.3 kg/s
b) 63.3 kg/s
c) 65.3 kg/s
d) 67.3 kg/s
Answer: b) 63.3 kg/s
23. If a hybrid rocket motor has a regression rate coefficient of 0.5 mm/(s·MPa^0.5) and operates at a
chamber pressure of 4 MPa, what is its regression rate?
a) 0.8 mm/s
b) 1.0 mm/s
c) 1.2 mm/s
d) 1.4 mm/s
Answer: b) 1.0 mm/s
24. A solid rocket booster produces 1.5 MN of thrust for 120 seconds. If its specific impulse is 250
seconds, how much propellant does it consume?
a) 7200 kg
b) 7400 kg
c) 7600 kg
d) 7800 kg
Answer: a) 7200 kg
25. If a liquid propellant rocket has a mixture ratio of 2.2:1 and uses 330 kg of propellant, how much
fuel is used?
a) 101.3 kg
b) 103.1 kg
c) 105.9 kg
d) 107.7 kg
Answer: b) 103.1 kg
26. A rocket engine has a chamber pressure of 10 MPa and an exit pressure of 50 kPa. What is its
pressure ratio?
a) 180
b) 190
c) 200
d) 210
Answer: c) 200
27. If a solid propellant has a density of 1700 kg/m³ and a rocket motor requires 800 kg of propellant,
what volume does the propellant occupy?
a) 0.451 m³
b) 0.461 m³
c) 0.471 m³
d) 0.481 m³
Answer: c) 0.471 m³
28. A liquid hydrogen/liquid oxygen rocket engine has a specific impulse of 450 seconds in vacuum.
What is its exhaust velocity?
a) 4313 m/s
b) 4413 m/s
c) 4513 m/s
d) 4613 m/s
Answer: b) 4413 m/s
29. If a hybrid rocket motor has a regression rate of 1.5 mm/s and burns for 40 seconds, how much of
the solid fuel is consumed (in thickness)?
a) 50 mm
b) 55 mm
c) 60 mm
d) 65 mm
Answer: c) 60 mm
30. A solid rocket motor has a propellant mass of 2000 kg and produces 400 kN of thrust for 30
seconds. What is its specific impulse?
a) 180 seconds
b) 190 seconds
c) 200 seconds
d) 210 seconds
Answer: c) 200 seconds
31. If a liquid propellant rocket engine has a thrust of 150 kN and a specific impulse of 330 seconds,
what is its propellant mass flow rate?
a) 45.5 kg/s
b) 46.5 kg/s
c) 47.5 kg/s
d) 48.5 kg/s
Answer: b) 46.5 kg/s
32. A hybrid rocket uses 75% solid fuel and 25% liquid oxidizer by mass. If the total propellant mass is
600 kg, how much liquid oxidizer is used?
a) 125 kg
b) 135 kg
c) 145 kg
d) 150 kg
Answer: d) 150 kg
33. If a solid propellant has a burning rate of 8 mm/s at a reference pressure of 5 MPa, and the
pressure exponent is 0.3, what is the burning rate at 8 MPa?
a) 9.1 mm/s
b) 9.3 mm/s
c) 9.5 mm/s
d) 9.7 mm/s
Answer: c) 9.5 mm/s
34. A liquid propellant rocket engine has a chamber temperature of 3200 K and a specific heat ratio
of 1.25. If the nozzle expansion ratio is 25, what is the thrust coefficient?
a) 1.75
b) 1.80
c) 1.85
d) 1.90
Answer: b) 1.80
35. If a solid rocket motor has a burn area of 1.5 m² and a propellant density of 1800 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 6 mm/s?
a) 15.5 kg/s
b) 16.2 kg/s
c) 16.9 kg/s
d) 17.6 kg/s
Answer: b) 16.2 kg/s
36. A liquid propellant rocket has a mixture ratio of 2.5:1 (oxidizer to fuel). If it consumes 100 kg of
fuel per second, what is the total propellant flow rate?
a) 330 kg/s
b) 340 kg/s
c) 350 kg/s
d) 360 kg/s
Answer: c) 350 kg/s
37. If a hybrid rocket motor has a fuel grain with an initial port diameter of 40 mm and a final port
diameter of 120 mm after burning, what is the average regression rate if the burn time is 25
seconds?
a) 1.4 mm/s
b) 1.6 mm/s
c) 1.8 mm/s
d) 2.0 mm/s
Answer: b) 1.6 mm/s
38. A solid propellant rocket has a propellant mass fraction of 0.88 and a total mass of 12,000 kg.
How much propellant does it contain?
a) 10,320 kg
b) 10,440 kg
c) 10,560 kg
d) 10,680 kg
Answer: c) 10,560 kg
39. If a liquid propellant rocket engine has a chamber pressure of 6 MPa and a throat area of 0.08 m²,
what is the mass flow rate if the characteristic velocity is 1600 m/s?
a) 290 kg/s
b) 300 kg/s
c) 310 kg/s
d) 320 kg/s
Answer: b) 300 kg/s
40. A hybrid rocket motor uses 60% of its oxidizer in the first 15 seconds of a 40-second burn. If the
total oxidizer mass is 800 kg, what is the average oxidizer flow rate for the last 25 seconds?
a) 11.2 kg/s
b) 12.2 kg/s
c) 12.8 kg/s
d) 13.2 kg/s
Answer: c) 12.8 kg/s
41. If a solid propellant has a density of 1750 kg/m³ and a specific heat of 1400 J/(kg·K), what is its
volumetric heat capacity?
a) 2.35 MJ/(m³·K)
b) 2.45 MJ/(m³·K)
c) 2.55 MJ/(m³·K)
d) 2.65 MJ/(m³·K)
Answer: b) 2.45 MJ/(m³·K)
42. A liquid propellant rocket engine has a thrust of 250 kN and a specific impulse of 340 seconds.
What is its propellant consumption rate?
a) 73.5 kg/s
b) 74.5 kg/s
c) 75.5 kg/s
d) 76.5 kg/s
Answer: c) 75.5 kg/s
A solid rocket motor has a propellant mass of 1000 kg and produces 250 kN of thrust for 40 seconds.
What is its specific impulse?
a) 220 seconds
b) 240 seconds
c) 260 seconds
d) 280 seconds
Answer: b) 240 seconds
11. If a liquid propellant rocket engine has a thrust of 100 kN and a specific impulse of 310 seconds,
what is its propellant mass flow rate?
a) 32.9 kg/s
b) 33.9 kg/s
c) 34.9 kg/s
d) 35.9 kg/s
Answer: a) 32.9 kg/s
12. A hybrid rocket uses 80% solid fuel and 20% liquid oxidizer by mass. If the total propellant mass is
500 kg, how much solid fuel is used?
a) 350 kg
b) 375 kg
c) 400 kg
d) 425 kg
Answer: c) 400 kg
13. If a solid propellant has a burning rate of 10 mm/s at a reference pressure of 7 MPa, and the
pressure exponent is 0.4, what is the burning rate at 10 MPa?
a) 11.5 mm/s
b) 12.0 mm/s
c) 12.5 mm/s
d) 13.0 mm/s
Answer: b) 12.0 mm/s
14. A liquid propellant rocket engine has a chamber temperature of 3500 K and a specific heat ratio
of 1.2. If the nozzle expansion ratio is 20, what is the thrust coefficient?
a) 1.59
b) 1.69
c) 1.79
d) 1.89
Answer: c) 1.79
15. If a solid rocket motor has a burn area of 2 m² and a propellant density of 1750 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 5 mm/s?
a) 15.5 kg/s
b) 16.5 kg/s
c) 17.5 kg/s
d) 18.5 kg/s
Answer: c) 17.5 kg/s
16. A liquid propellant rocket has a mixture ratio of 3:1 (oxidizer to fuel). If it consumes 80 kg of fuel
per second, what is the total propellant flow rate?
a) 300 kg/s
b) 310 kg/s
c) 320 kg/s
d) 330 kg/s
Answer: c) 320 kg/s
17. If a hybrid rocket motor has a fuel grain with an initial port diameter of 50 mm and a final port
diameter of 150 mm after burning, what is the average regression rate if the burn time is 30
seconds?
a) 1.33 mm/s
b) 1.67 mm/s
c) 2.00 mm/s
d) 2.33 mm/s
Answer: b) 1.67 mm/s
18. A solid propellant rocket has a propellant mass fraction of 0.85 and a total mass of 10,000 kg.
How much propellant does it contain?
a) 7500 kg
b) 8000 kg
c) 8500 kg
d) 9000 kg
Answer: c) 8500 kg
19. If a liquid propellant rocket engine has a chamber pressure of 5 MPa and a throat area of 0.1 m²,
what is the mass flow rate if the characteristic velocity is 1500 m/s?
a) 323 kg/s
b) 333 kg/s
c) 343 kg/s
d) 353 kg/s
Answer: b) 333 kg/s
20. A hybrid rocket motor uses 70% of its oxidizer in the first 20 seconds of a 50-second burn. If the
total oxidizer mass is 1000 kg, what is the average oxidizer flow rate for the last 30 seconds?
a) 8 kg/s
b) 9 kg/s
c) 10 kg/s
d) 11 kg/s
Answer: c) 10 kg/s
21. If a solid propellant has a density of 1800 kg/m³ and a specific heat of 1500 J/(kg·K), what is its
volumetric heat capacity?
a) 2.5 MJ/(m³·K)
b) 2.7 MJ/(m³·K)
c) 2.9 MJ/(m³·K)
d) 3.1 MJ/(m³·K)
Answer: b) 2.7 MJ/(m³·K)
22. A liquid propellant rocket engine has a thrust of 200 kN and a specific impulse of 320 seconds.
What is its propellant consumption rate?
a) 61.3 kg/s
b) 63.3 kg/s
c) 65.3 kg/s
d) 67.3 kg/s
Answer: b) 63.3 kg/s
23. If a hybrid rocket motor has a regression rate coefficient of 0.5 mm/(s·MPa^0.5) and operates at a
chamber pressure of 4 MPa, what is its regression rate?
a) 0.8 mm/s
b) 1.0 mm/s
c) 1.2 mm/s
d) 1.4 mm/s
Answer: b) 1.0 mm/s
24. A solid rocket booster produces 1.5 MN of thrust for 120 seconds. If its specific impulse is 250
seconds, how much propellant does it consume?
a) 7200 kg
b) 7400 kg
c) 7600 kg
d) 7800 kg
Answer: a) 7200 kg
25. If a liquid propellant rocket has a mixture ratio of 2.2:1 and uses 330 kg of propellant, how much
fuel is used?
a) 101.3 kg
b) 103.1 kg
c) 105.9 kg
d) 107.7 kg
Answer: b) 103.1 kg
26. A rocket engine has a chamber pressure of 10 MPa and an exit pressure of 50 kPa. What is its
pressure ratio?
a) 180
b) 190
c) 200
d) 210
Answer: c) 200
27. If a solid propellant has a density of 1700 kg/m³ and a rocket motor requires 800 kg of propellant,
what volume does the propellant occupy?
a) 0.451 m³
b) 0.461 m³
c) 0.471 m³
d) 0.481 m³
Answer: c) 0.471 m³
28. A liquid hydrogen/liquid oxygen rocket engine has a specific impulse of 450 seconds in vacuum.
What is its exhaust velocity?
a) 4313 m/s
b) 4413 m/s
c) 4513 m/s
d) 4613 m/s
Answer: b) 4413 m/s
29. If a hybrid rocket motor has a regression rate of 1.5 mm/s and burns for 40 seconds, how much of
the solid fuel is consumed (in thickness)?
a) 50 mm
b) 55 mm
c) 60 mm
d) 65 mm
Answer: c) 60 mm
30. A solid rocket motor has a propellant mass of 2000 kg and produces 400 kN of thrust for 30
seconds. What is its specific impulse?
a) 180 seconds
b) 190 seconds
c) 200 seconds
d) 210 seconds
Answer: c) 200 seconds
31. If a liquid propellant rocket engine has a thrust of 150 kN and a specific impulse of 330 seconds,
what is its propellant mass flow rate?
a) 45.5 kg/s
b) 46.5 kg/s
c) 47.5 kg/s
d) 48.5 kg/s
Answer: b) 46.5 kg/s
32. A hybrid rocket uses 75% solid fuel and 25% liquid oxidizer by mass. If the total propellant mass is
600 kg, how much liquid oxidizer is used?
a) 125 kg
b) 135 kg
c) 145 kg
d) 150 kg
Answer: d) 150 kg
33. If a solid propellant has a burning rate of 8 mm/s at a reference pressure of 5 MPa, and the
pressure exponent is 0.3, what is the burning rate at 8 MPa?
a) 9.1 mm/s
b) 9.3 mm/s
c) 9.5 mm/s
d) 9.7 mm/s
Answer: c) 9.5 mm/s
34. A liquid propellant rocket engine has a chamber temperature of 3200 K and a specific heat ratio
of 1.25. If the nozzle expansion ratio is 25, what is the thrust coefficient?
a) 1.75
b) 1.80
c) 1.85
d) 1.90
Answer: b) 1.80
35. If a solid rocket motor has a burn area of 1.5 m² and a propellant density of 1800 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 6 mm/s?
a) 15.5 kg/s
b) 16.2 kg/s
c) 16.9 kg/s
d) 17.6 kg/s
Answer: b) 16.2 kg/s
36. A liquid propellant rocket has a mixture ratio of 2.5:1 (oxidizer to fuel). If it consumes 100 kg of
fuel per second, what is the total propellant flow rate?
a) 330 kg/s
b) 340 kg/s
c) 350 kg/s
d) 360 kg/s
Answer: c) 350 kg/s
37. If a hybrid rocket motor has a fuel grain with an initial port diameter of 40 mm and a final port
diameter of 120 mm after burning, what is the average regression rate if the burn time is 25
seconds?
a) 1.4 mm/s
b) 1.6 mm/s
c) 1.8 mm/s
d) 2.0 mm/s
Answer: b) 1.6 mm/s
38. A solid propellant rocket has a propellant mass fraction of 0.88 and a total mass of 12,000 kg.
How much propellant does it contain?
a) 10,320 kg
b) 10,440 kg
c) 10,560 kg
d) 10,680 kg
Answer: c) 10,560 kg
39. If a liquid propellant rocket engine has a chamber pressure of 6 MPa and a throat area of 0.08 m²,
what is the mass flow rate if the characteristic velocity is 1600 m/s?
a) 290 kg/s
b) 300 kg/s
c) 310 kg/s
d) 320 kg/s
Answer: b) 300 kg/s
40. A hybrid rocket motor uses 60% of its oxidizer in the first 15 seconds of a 40-second burn. If the
total oxidizer mass is 800 kg, what is the average oxidizer flow rate for the last 25 seconds?
a) 11.2 kg/s
b) 12.2 kg/s
c) 12.8 kg/s
d) 13.2 kg/s
Answer: c) 12.8 kg/s
41. If a solid propellant has a density of 1750 kg/m³ and a specific heat of 1400 J/(kg·K), what is its
volumetric heat capacity?
a) 2.35 MJ/(m³·K)
b) 2.45 MJ/(m³·K)
c) 2.55 MJ/(m³·K)
d) 2.65 MJ/(m³·K)
Answer: b) 2.45 MJ/(m³·K)
42. A liquid propellant rocket engine has a thrust of 250 kN and a specific impulse of 340 seconds.
What is its propellant consumption rate?
a) 73.5 kg/s
b) 74.5 kg/s
c) 75.5 kg/s
d) 76.5 kg/s
Answer: c) 75.5 kg/s
A solid rocket motor has a propellant mass of 1000 kg and produces 250 kN of thrust for 40 seconds.
What is its specific impulse?
a) 220 seconds
b) 240 seconds
c) 260 seconds
d) 280 seconds
Answer: b) 240 seconds
11. If a liquid propellant rocket engine has a thrust of 100 kN and a specific impulse of 310 seconds,
what is its propellant mass flow rate?
a) 32.9 kg/s
b) 33.9 kg/s
c) 34.9 kg/s
d) 35.9 kg/s
Answer: a) 32.9 kg/s
12. A hybrid rocket uses 80% solid fuel and 20% liquid oxidizer by mass. If the total propellant mass is
500 kg, how much solid fuel is used?
a) 350 kg
b) 375 kg
c) 400 kg
d) 425 kg
Answer: c) 400 kg
13. If a solid propellant has a burning rate of 10 mm/s at a reference pressure of 7 MPa, and the
pressure exponent is 0.4, what is the burning rate at 10 MPa?
a) 11.5 mm/s
b) 12.0 mm/s
c) 12.5 mm/s
d) 13.0 mm/s
Answer: b) 12.0 mm/s
14. A liquid propellant rocket engine has a chamber temperature of 3500 K and a specific heat ratio
of 1.2. If the nozzle expansion ratio is 20, what is the thrust coefficient?
a) 1.59
b) 1.69
c) 1.79
d) 1.89
Answer: c) 1.79
15. If a solid rocket motor has a burn area of 2 m² and a propellant density of 1750 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 5 mm/s?
a) 15.5 kg/s
b) 16.5 kg/s
c) 17.5 kg/s
d) 18.5 kg/s
Answer: c) 17.5 kg/s
16. A liquid propellant rocket has a mixture ratio of 3:1 (oxidizer to fuel). If it consumes 80 kg of fuel
per second, what is the total propellant flow rate?
a) 300 kg/s
b) 310 kg/s
c) 320 kg/s
d) 330 kg/s
Answer: c) 320 kg/s
17. If a hybrid rocket motor has a fuel grain with an initial port diameter of 50 mm and a final port
diameter of 150 mm after burning, what is the average regression rate if the burn time is 30
seconds?
a) 1.33 mm/s
b) 1.67 mm/s
c) 2.00 mm/s
d) 2.33 mm/s
Answer: b) 1.67 mm/s
18. A solid propellant rocket has a propellant mass fraction of 0.85 and a total mass of 10,000 kg.
How much propellant does it contain?
a) 7500 kg
b) 8000 kg
c) 8500 kg
d) 9000 kg
Answer: c) 8500 kg
19. If a liquid propellant rocket engine has a chamber pressure of 5 MPa and a throat area of 0.1 m²,
what is the mass flow rate if the characteristic velocity is 1500 m/s?
a) 323 kg/s
b) 333 kg/s
c) 343 kg/s
d) 353 kg/s
Answer: b) 333 kg/s
20. A hybrid rocket motor uses 70% of its oxidizer in the first 20 seconds of a 50-second burn. If the
total oxidizer mass is 1000 kg, what is the average oxidizer flow rate for the last 30 seconds?
a) 8 kg/s
b) 9 kg/s
c) 10 kg/s
d) 11 kg/s
Answer: c) 10 kg/s
21. If a solid propellant has a density of 1800 kg/m³ and a specific heat of 1500 J/(kg·K), what is its
volumetric heat capacity?
a) 2.5 MJ/(m³·K)
b) 2.7 MJ/(m³·K)
c) 2.9 MJ/(m³·K)
d) 3.1 MJ/(m³·K)
Answer: b) 2.7 MJ/(m³·K)
22. A liquid propellant rocket engine has a thrust of 200 kN and a specific impulse of 320 seconds.
What is its propellant consumption rate?
a) 61.3 kg/s
b) 63.3 kg/s
c) 65.3 kg/s
d) 67.3 kg/s
Answer: b) 63.3 kg/s
23. If a hybrid rocket motor has a regression rate coefficient of 0.5 mm/(s·MPa^0.5) and operates at a
chamber pressure of 4 MPa, what is its regression rate?
a) 0.8 mm/s
b) 1.0 mm/s
c) 1.2 mm/s
d) 1.4 mm/s
Answer: b) 1.0 mm/s
24. A solid rocket booster produces 1.5 MN of thrust for 120 seconds. If its specific impulse is 250
seconds, how much propellant does it consume?
a) 7200 kg
b) 7400 kg
c) 7600 kg
d) 7800 kg
Answer: a) 7200 kg
25. If a liquid propellant rocket has a mixture ratio of 2.2:1 and uses 330 kg of propellant, how much
fuel is used?
a) 101.3 kg
b) 103.1 kg
c) 105.9 kg
d) 107.7 kg
Answer: b) 103.1 kg
26. A rocket engine has a chamber pressure of 10 MPa and an exit pressure of 50 kPa. What is its
pressure ratio?
a) 180
b) 190
c) 200
d) 210
Answer: c) 200
27. If a solid propellant has a density of 1700 kg/m³ and a rocket motor requires 800 kg of propellant,
what volume does the propellant occupy?
a) 0.451 m³
b) 0.461 m³
c) 0.471 m³
d) 0.481 m³
Answer: c) 0.471 m³
28. A liquid hydrogen/liquid oxygen rocket engine has a specific impulse of 450 seconds in vacuum.
What is its exhaust velocity?
a) 4313 m/s
b) 4413 m/s
c) 4513 m/s
d) 4613 m/s
Answer: b) 4413 m/s
29. If a hybrid rocket motor has a regression rate of 1.5 mm/s and burns for 40 seconds, how much of
the solid fuel is consumed (in thickness)?
a) 50 mm
b) 55 mm
c) 60 mm
d) 65 mm
Answer: c) 60 mm
30. A solid rocket motor has a propellant mass of 2000 kg and produces 400 kN of thrust for 30
seconds. What is its specific impulse?
a) 180 seconds
b) 190 seconds
c) 200 seconds
d) 210 seconds
Answer: c) 200 seconds
31. If a liquid propellant rocket engine has a thrust of 150 kN and a specific impulse of 330 seconds,
what is its propellant mass flow rate?
a) 45.5 kg/s
b) 46.5 kg/s
c) 47.5 kg/s
d) 48.5 kg/s
Answer: b) 46.5 kg/s
32. A hybrid rocket uses 75% solid fuel and 25% liquid oxidizer by mass. If the total propellant mass is
600 kg, how much liquid oxidizer is used?
a) 125 kg
b) 135 kg
c) 145 kg
d) 150 kg
Answer: d) 150 kg
33. If a solid propellant has a burning rate of 8 mm/s at a reference pressure of 5 MPa, and the
pressure exponent is 0.3, what is the burning rate at 8 MPa?
a) 9.1 mm/s
b) 9.3 mm/s
c) 9.5 mm/s
d) 9.7 mm/s
Answer: c) 9.5 mm/s
34. A liquid propellant rocket engine has a chamber temperature of 3200 K and a specific heat ratio
of 1.25. If the nozzle expansion ratio is 25, what is the thrust coefficient?
a) 1.75
b) 1.80
c) 1.85
d) 1.90
Answer: b) 1.80
35. If a solid rocket motor has a burn area of 1.5 m² and a propellant density of 1800 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 6 mm/s?
a) 15.5 kg/s
b) 16.2 kg/s
c) 16.9 kg/s
d) 17.6 kg/s
Answer: b) 16.2 kg/s
36. A liquid propellant rocket has a mixture ratio of 2.5:1 (oxidizer to fuel). If it consumes 100 kg of
fuel per second, what is the total propellant flow rate?
a) 330 kg/s
b) 340 kg/s
c) 350 kg/s
d) 360 kg/s
Answer: c) 350 kg/s
37. If a hybrid rocket motor has a fuel grain with an initial port diameter of 40 mm and a final port
diameter of 120 mm after burning, what is the average regression rate if the burn time is 25
seconds?
a) 1.4 mm/s
b) 1.6 mm/s
c) 1.8 mm/s
d) 2.0 mm/s
Answer: b) 1.6 mm/s
38. A solid propellant rocket has a propellant mass fraction of 0.88 and a total mass of 12,000 kg.
How much propellant does it contain?
a) 10,320 kg
b) 10,440 kg
c) 10,560 kg
d) 10,680 kg
Answer: c) 10,560 kg
39. If a liquid propellant rocket engine has a chamber pressure of 6 MPa and a throat area of 0.08 m²,
what is the mass flow rate if the characteristic velocity is 1600 m/s?
a) 290 kg/s
b) 300 kg/s
c) 310 kg/s
d) 320 kg/s
Answer: b) 300 kg/s
40. A hybrid rocket motor uses 60% of its oxidizer in the first 15 seconds of a 40-second burn. If the
total oxidizer mass is 800 kg, what is the average oxidizer flow rate for the last 25 seconds?
a) 11.2 kg/s
b) 12.2 kg/s
c) 12.8 kg/s
d) 13.2 kg/s
Answer: c) 12.8 kg/s
41. If a solid propellant has a density of 1750 kg/m³ and a specific heat of 1400 J/(kg·K), what is its
volumetric heat capacity?
a) 2.35 MJ/(m³·K)
b) 2.45 MJ/(m³·K)
c) 2.55 MJ/(m³·K)
d) 2.65 MJ/(m³·K)
Answer: b) 2.45 MJ/(m³·K)
42. A liquid propellant rocket engine has a thrust of 250 kN and a specific impulse of 340 seconds.
What is its propellant consumption rate?
a) 73.5 kg/s
b) 74.5 kg/s
c) 75.5 kg/s
d) 76.5 kg/s
Answer: c) 75.5 kg/s
A solid rocket motor has a propellant mass of 1000 kg and produces 250 kN of thrust for 40 seconds.
What is its specific impulse?
a) 220 seconds
b) 240 seconds
c) 260 seconds
d) 280 seconds
Answer: b) 240 seconds
11. If a liquid propellant rocket engine has a thrust of 100 kN and a specific impulse of 310 seconds,
what is its propellant mass flow rate?
a) 32.9 kg/s
b) 33.9 kg/s
c) 34.9 kg/s
d) 35.9 kg/s
Answer: a) 32.9 kg/s
12. A hybrid rocket uses 80% solid fuel and 20% liquid oxidizer by mass. If the total propellant mass is
500 kg, how much solid fuel is used?
a) 350 kg
b) 375 kg
c) 400 kg
d) 425 kg
Answer: c) 400 kg
13. If a solid propellant has a burning rate of 10 mm/s at a reference pressure of 7 MPa, and the
pressure exponent is 0.4, what is the burning rate at 10 MPa?
a) 11.5 mm/s
b) 12.0 mm/s
c) 12.5 mm/s
d) 13.0 mm/s
Answer: b) 12.0 mm/s
14. A liquid propellant rocket engine has a chamber temperature of 3500 K and a specific heat ratio
of 1.2. If the nozzle expansion ratio is 20, what is the thrust coefficient?
a) 1.59
b) 1.69
c) 1.79
d) 1.89
Answer: c) 1.79
15. If a solid rocket motor has a burn area of 2 m² and a propellant density of 1750 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 5 mm/s?
a) 15.5 kg/s
b) 16.5 kg/s
c) 17.5 kg/s
d) 18.5 kg/s
Answer: c) 17.5 kg/s
16. A liquid propellant rocket has a mixture ratio of 3:1 (oxidizer to fuel). If it consumes 80 kg of fuel
per second, what is the total propellant flow rate?
a) 300 kg/s
b) 310 kg/s
c) 320 kg/s
d) 330 kg/s
Answer: c) 320 kg/s
17. If a hybrid rocket motor has a fuel grain with an initial port diameter of 50 mm and a final port
diameter of 150 mm after burning, what is the average regression rate if the burn time is 30
seconds?
a) 1.33 mm/s
b) 1.67 mm/s
c) 2.00 mm/s
d) 2.33 mm/s
Answer: b) 1.67 mm/s
18. A solid propellant rocket has a propellant mass fraction of 0.85 and a total mass of 10,000 kg.
How much propellant does it contain?
a) 7500 kg
b) 8000 kg
c) 8500 kg
d) 9000 kg
Answer: c) 8500 kg
19. If a liquid propellant rocket engine has a chamber pressure of 5 MPa and a throat area of 0.1 m²,
what is the mass flow rate if the characteristic velocity is 1500 m/s?
a) 323 kg/s
b) 333 kg/s
c) 343 kg/s
d) 353 kg/s
Answer: b) 333 kg/s
20. A hybrid rocket motor uses 70% of its oxidizer in the first 20 seconds of a 50-second burn. If the
total oxidizer mass is 1000 kg, what is the average oxidizer flow rate for the last 30 seconds?
a) 8 kg/s
b) 9 kg/s
c) 10 kg/s
d) 11 kg/s
Answer: c) 10 kg/s
21. If a solid propellant has a density of 1800 kg/m³ and a specific heat of 1500 J/(kg·K), what is its
volumetric heat capacity?
a) 2.5 MJ/(m³·K)
b) 2.7 MJ/(m³·K)
c) 2.9 MJ/(m³·K)
d) 3.1 MJ/(m³·K)
Answer: b) 2.7 MJ/(m³·K)
22. A liquid propellant rocket engine has a thrust of 200 kN and a specific impulse of 320 seconds.
What is its propellant consumption rate?
a) 61.3 kg/s
b) 63.3 kg/s
c) 65.3 kg/s
d) 67.3 kg/s
Answer: b) 63.3 kg/s
23. If a hybrid rocket motor has a regression rate coefficient of 0.5 mm/(s·MPa^0.5) and operates at a
chamber pressure of 4 MPa, what is its regression rate?
a) 0.8 mm/s
b) 1.0 mm/s
c) 1.2 mm/s
d) 1.4 mm/s
Answer: b) 1.0 mm/s
24. A solid rocket booster produces 1.5 MN of thrust for 120 seconds. If its specific impulse is 250
seconds, how much propellant does it consume?
a) 7200 kg
b) 7400 kg
c) 7600 kg
d) 7800 kg
Answer: a) 7200 kg
25. If a liquid propellant rocket has a mixture ratio of 2.2:1 and uses 330 kg of propellant, how much
fuel is used?
a) 101.3 kg
b) 103.1 kg
c) 105.9 kg
d) 107.7 kg
Answer: b) 103.1 kg
26. A rocket engine has a chamber pressure of 10 MPa and an exit pressure of 50 kPa. What is its
pressure ratio?
a) 180
b) 190
c) 200
d) 210
Answer: c) 200
27. If a solid propellant has a density of 1700 kg/m³ and a rocket motor requires 800 kg of propellant,
what volume does the propellant occupy?
a) 0.451 m³
b) 0.461 m³
c) 0.471 m³
d) 0.481 m³
Answer: c) 0.471 m³
28. A liquid hydrogen/liquid oxygen rocket engine has a specific impulse of 450 seconds in vacuum.
What is its exhaust velocity?
a) 4313 m/s
b) 4413 m/s
c) 4513 m/s
d) 4613 m/s
Answer: b) 4413 m/s
29. If a hybrid rocket motor has a regression rate of 1.5 mm/s and burns for 40 seconds, how much of
the solid fuel is consumed (in thickness)?
a) 50 mm
b) 55 mm
c) 60 mm
d) 65 mm
Answer: c) 60 mm
30. A solid rocket motor has a propellant mass of 2000 kg and produces 400 kN of thrust for 30
seconds. What is its specific impulse?
a) 180 seconds
b) 190 seconds
c) 200 seconds
d) 210 seconds
Answer: c) 200 seconds
31. If a liquid propellant rocket engine has a thrust of 150 kN and a specific impulse of 330 seconds,
what is its propellant mass flow rate?
a) 45.5 kg/s
b) 46.5 kg/s
c) 47.5 kg/s
d) 48.5 kg/s
Answer: b) 46.5 kg/s
32. A hybrid rocket uses 75% solid fuel and 25% liquid oxidizer by mass. If the total propellant mass is
600 kg, how much liquid oxidizer is used?
a) 125 kg
b) 135 kg
c) 145 kg
d) 150 kg
Answer: d) 150 kg
33. If a solid propellant has a burning rate of 8 mm/s at a reference pressure of 5 MPa, and the
pressure exponent is 0.3, what is the burning rate at 8 MPa?
a) 9.1 mm/s
b) 9.3 mm/s
c) 9.5 mm/s
d) 9.7 mm/s
Answer: c) 9.5 mm/s
34. A liquid propellant rocket engine has a chamber temperature of 3200 K and a specific heat ratio
of 1.25. If the nozzle expansion ratio is 25, what is the thrust coefficient?
a) 1.75
b) 1.80
c) 1.85
d) 1.90
Answer: b) 1.80
35. If a solid rocket motor has a burn area of 1.5 m² and a propellant density of 1800 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 6 mm/s?
a) 15.5 kg/s
b) 16.2 kg/s
c) 16.9 kg/s
d) 17.6 kg/s
Answer: b) 16.2 kg/s
36. A liquid propellant rocket has a mixture ratio of 2.5:1 (oxidizer to fuel). If it consumes 100 kg of
fuel per second, what is the total propellant flow rate?
a) 330 kg/s
b) 340 kg/s
c) 350 kg/s
d) 360 kg/s
Answer: c) 350 kg/s
37. If a hybrid rocket motor has a fuel grain with an initial port diameter of 40 mm and a final port
diameter of 120 mm after burning, what is the average regression rate if the burn time is 25
seconds?
a) 1.4 mm/s
b) 1.6 mm/s
c) 1.8 mm/s
d) 2.0 mm/s
Answer: b) 1.6 mm/s
38. A solid propellant rocket has a propellant mass fraction of 0.88 and a total mass of 12,000 kg.
How much propellant does it contain?
a) 10,320 kg
b) 10,440 kg
c) 10,560 kg
d) 10,680 kg
Answer: c) 10,560 kg
39. If a liquid propellant rocket engine has a chamber pressure of 6 MPa and a throat area of 0.08 m²,
what is the mass flow rate if the characteristic velocity is 1600 m/s?
a) 290 kg/s
b) 300 kg/s
c) 310 kg/s
d) 320 kg/s
Answer: b) 300 kg/s
40. A hybrid rocket motor uses 60% of its oxidizer in the first 15 seconds of a 40-second burn. If the
total oxidizer mass is 800 kg, what is the average oxidizer flow rate for the last 25 seconds?
a) 11.2 kg/s
b) 12.2 kg/s
c) 12.8 kg/s
d) 13.2 kg/s
Answer: c) 12.8 kg/s
41. If a solid propellant has a density of 1750 kg/m³ and a specific heat of 1400 J/(kg·K), what is its
volumetric heat capacity?
a) 2.35 MJ/(m³·K)
b) 2.45 MJ/(m³·K)
c) 2.55 MJ/(m³·K)
d) 2.65 MJ/(m³·K)
Answer: b) 2.45 MJ/(m³·K)
42. A liquid propellant rocket engine has a thrust of 250 kN and a specific impulse of 340 seconds.
What is its propellant consumption rate?
a) 73.5 kg/s
b) 74.5 kg/s
c) 75.5 kg/s
d) 76.5 kg/s
Answer: c) 75.5 kg/s
A solid rocket motor has a propellant mass of 1000 kg and produces 250 kN of thrust for 40 seconds.
What is its specific impulse?
a) 220 seconds
b) 240 seconds
c) 260 seconds
d) 280 seconds
Answer: b) 240 seconds
11. If a liquid propellant rocket engine has a thrust of 100 kN and a specific impulse of 310 seconds,
what is its propellant mass flow rate?
a) 32.9 kg/s
b) 33.9 kg/s
c) 34.9 kg/s
d) 35.9 kg/s
Answer: a) 32.9 kg/s
12. A hybrid rocket uses 80% solid fuel and 20% liquid oxidizer by mass. If the total propellant mass is
500 kg, how much solid fuel is used?
a) 350 kg
b) 375 kg
c) 400 kg
d) 425 kg
Answer: c) 400 kg
13. If a solid propellant has a burning rate of 10 mm/s at a reference pressure of 7 MPa, and the
pressure exponent is 0.4, what is the burning rate at 10 MPa?
a) 11.5 mm/s
b) 12.0 mm/s
c) 12.5 mm/s
d) 13.0 mm/s
Answer: b) 12.0 mm/s
14. A liquid propellant rocket engine has a chamber temperature of 3500 K and a specific heat ratio
of 1.2. If the nozzle expansion ratio is 20, what is the thrust coefficient?
a) 1.59
b) 1.69
c) 1.79
d) 1.89
Answer: c) 1.79
15. If a solid rocket motor has a burn area of 2 m² and a propellant density of 1750 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 5 mm/s?
a) 15.5 kg/s
b) 16.5 kg/s
c) 17.5 kg/s
d) 18.5 kg/s
Answer: c) 17.5 kg/s
16. A liquid propellant rocket has a mixture ratio of 3:1 (oxidizer to fuel). If it consumes 80 kg of fuel
per second, what is the total propellant flow rate?
a) 300 kg/s
b) 310 kg/s
c) 320 kg/s
d) 330 kg/s
Answer: c) 320 kg/s
17. If a hybrid rocket motor has a fuel grain with an initial port diameter of 50 mm and a final port
diameter of 150 mm after burning, what is the average regression rate if the burn time is 30
seconds?
a) 1.33 mm/s
b) 1.67 mm/s
c) 2.00 mm/s
d) 2.33 mm/s
Answer: b) 1.67 mm/s
18. A solid propellant rocket has a propellant mass fraction of 0.85 and a total mass of 10,000 kg.
How much propellant does it contain?
a) 7500 kg
b) 8000 kg
c) 8500 kg
d) 9000 kg
Answer: c) 8500 kg
19. If a liquid propellant rocket engine has a chamber pressure of 5 MPa and a throat area of 0.1 m²,
what is the mass flow rate if the characteristic velocity is 1500 m/s?
a) 323 kg/s
b) 333 kg/s
c) 343 kg/s
d) 353 kg/s
Answer: b) 333 kg/s
20. A hybrid rocket motor uses 70% of its oxidizer in the first 20 seconds of a 50-second burn. If the
total oxidizer mass is 1000 kg, what is the average oxidizer flow rate for the last 30 seconds?
a) 8 kg/s
b) 9 kg/s
c) 10 kg/s
d) 11 kg/s
Answer: c) 10 kg/s
21. If a solid propellant has a density of 1800 kg/m³ and a specific heat of 1500 J/(kg·K), what is its
volumetric heat capacity?
a) 2.5 MJ/(m³·K)
b) 2.7 MJ/(m³·K)
c) 2.9 MJ/(m³·K)
d) 3.1 MJ/(m³·K)
Answer: b) 2.7 MJ/(m³·K)
22. A liquid propellant rocket engine has a thrust of 200 kN and a specific impulse of 320 seconds.
What is its propellant consumption rate?
a) 61.3 kg/s
b) 63.3 kg/s
c) 65.3 kg/s
d) 67.3 kg/s
Answer: b) 63.3 kg/s
23. If a hybrid rocket motor has a regression rate coefficient of 0.5 mm/(s·MPa^0.5) and operates at a
chamber pressure of 4 MPa, what is its regression rate?
a) 0.8 mm/s
b) 1.0 mm/s
c) 1.2 mm/s
d) 1.4 mm/s
Answer: b) 1.0 mm/s
24. A solid rocket booster produces 1.5 MN of thrust for 120 seconds. If its specific impulse is 250
seconds, how much propellant does it consume?
a) 7200 kg
b) 7400 kg
c) 7600 kg
d) 7800 kg
Answer: a) 7200 kg
25. If a liquid propellant rocket has a mixture ratio of 2.2:1 and uses 330 kg of propellant, how much
fuel is used?
a) 101.3 kg
b) 103.1 kg
c) 105.9 kg
d) 107.7 kg
Answer: b) 103.1 kg
26. A rocket engine has a chamber pressure of 10 MPa and an exit pressure of 50 kPa. What is its
pressure ratio?
a) 180
b) 190
c) 200
d) 210
Answer: c) 200
27. If a solid propellant has a density of 1700 kg/m³ and a rocket motor requires 800 kg of propellant,
what volume does the propellant occupy?
a) 0.451 m³
b) 0.461 m³
c) 0.471 m³
d) 0.481 m³
Answer: c) 0.471 m³
28. A liquid hydrogen/liquid oxygen rocket engine has a specific impulse of 450 seconds in vacuum.
What is its exhaust velocity?
a) 4313 m/s
b) 4413 m/s
c) 4513 m/s
d) 4613 m/s
Answer: b) 4413 m/s
29. If a hybrid rocket motor has a regression rate of 1.5 mm/s and burns for 40 seconds, how much of
the solid fuel is consumed (in thickness)?
a) 50 mm
b) 55 mm
c) 60 mm
d) 65 mm
Answer: c) 60 mm
30. A solid rocket motor has a propellant mass of 2000 kg and produces 400 kN of thrust for 30
seconds. What is its specific impulse?
a) 180 seconds
b) 190 seconds
c) 200 seconds
d) 210 seconds
Answer: c) 200 seconds
31. If a liquid propellant rocket engine has a thrust of 150 kN and a specific impulse of 330 seconds,
what is its propellant mass flow rate?
a) 45.5 kg/s
b) 46.5 kg/s
c) 47.5 kg/s
d) 48.5 kg/s
Answer: b) 46.5 kg/s
32. A hybrid rocket uses 75% solid fuel and 25% liquid oxidizer by mass. If the total propellant mass is
600 kg, how much liquid oxidizer is used?
a) 125 kg
b) 135 kg
c) 145 kg
d) 150 kg
Answer: d) 150 kg
33. If a solid propellant has a burning rate of 8 mm/s at a reference pressure of 5 MPa, and the
pressure exponent is 0.3, what is the burning rate at 8 MPa?
a) 9.1 mm/s
b) 9.3 mm/s
c) 9.5 mm/s
d) 9.7 mm/s
Answer: c) 9.5 mm/s
34. A liquid propellant rocket engine has a chamber temperature of 3200 K and a specific heat ratio
of 1.25. If the nozzle expansion ratio is 25, what is the thrust coefficient?
a) 1.75
b) 1.80
c) 1.85
d) 1.90
Answer: b) 1.80
35. If a solid rocket motor has a burn area of 1.5 m² and a propellant density of 1800 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 6 mm/s?
a) 15.5 kg/s
b) 16.2 kg/s
c) 16.9 kg/s
d) 17.6 kg/s
Answer: b) 16.2 kg/s
36. A liquid propellant rocket has a mixture ratio of 2.5:1 (oxidizer to fuel). If it consumes 100 kg of
fuel per second, what is the total propellant flow rate?
a) 330 kg/s
b) 340 kg/s
c) 350 kg/s
d) 360 kg/s
Answer: c) 350 kg/s
37. If a hybrid rocket motor has a fuel grain with an initial port diameter of 40 mm and a final port
diameter of 120 mm after burning, what is the average regression rate if the burn time is 25
seconds?
a) 1.4 mm/s
b) 1.6 mm/s
c) 1.8 mm/s
d) 2.0 mm/s
Answer: b) 1.6 mm/s
38. A solid propellant rocket has a propellant mass fraction of 0.88 and a total mass of 12,000 kg.
How much propellant does it contain?
a) 10,320 kg
b) 10,440 kg
c) 10,560 kg
d) 10,680 kg
Answer: c) 10,560 kg
39. If a liquid propellant rocket engine has a chamber pressure of 6 MPa and a throat area of 0.08 m²,
what is the mass flow rate if the characteristic velocity is 1600 m/s?
a) 290 kg/s
b) 300 kg/s
c) 310 kg/s
d) 320 kg/s
Answer: b) 300 kg/s
40. A hybrid rocket motor uses 60% of its oxidizer in the first 15 seconds of a 40-second burn. If the
total oxidizer mass is 800 kg, what is the average oxidizer flow rate for the last 25 seconds?
a) 11.2 kg/s
b) 12.2 kg/s
c) 12.8 kg/s
d) 13.2 kg/s
Answer: c) 12.8 kg/s
41. If a solid propellant has a density of 1750 kg/m³ and a specific heat of 1400 J/(kg·K), what is its
volumetric heat capacity?
a) 2.35 MJ/(m³·K)
b) 2.45 MJ/(m³·K)
c) 2.55 MJ/(m³·K)
d) 2.65 MJ/(m³·K)
Answer: b) 2.45 MJ/(m³·K)
42. A liquid propellant rocket engine has a thrust of 250 kN and a specific impulse of 340 seconds.
What is its propellant consumption rate?
a) 73.5 kg/s
b) 74.5 kg/s
c) 75.5 kg/s
d) 76.5 kg/s
Answer: c) 75.5 kg/s
A solid rocket motor has a propellant mass of 1000 kg and produces 250 kN of thrust for 40 seconds.
What is its specific impulse?
a) 220 seconds
b) 240 seconds
c) 260 seconds
d) 280 seconds
Answer: b) 240 seconds
11. If a liquid propellant rocket engine has a thrust of 100 kN and a specific impulse of 310 seconds,
what is its propellant mass flow rate?
a) 32.9 kg/s
b) 33.9 kg/s
c) 34.9 kg/s
d) 35.9 kg/s
Answer: a) 32.9 kg/s
12. A hybrid rocket uses 80% solid fuel and 20% liquid oxidizer by mass. If the total propellant mass is
500 kg, how much solid fuel is used?
a) 350 kg
b) 375 kg
c) 400 kg
d) 425 kg
Answer: c) 400 kg
13. If a solid propellant has a burning rate of 10 mm/s at a reference pressure of 7 MPa, and the
pressure exponent is 0.4, what is the burning rate at 10 MPa?
a) 11.5 mm/s
b) 12.0 mm/s
c) 12.5 mm/s
d) 13.0 mm/s
Answer: b) 12.0 mm/s
14. A liquid propellant rocket engine has a chamber temperature of 3500 K and a specific heat ratio
of 1.2. If the nozzle expansion ratio is 20, what is the thrust coefficient?
a) 1.59
b) 1.69
c) 1.79
d) 1.89
Answer: c) 1.79
15. If a solid rocket motor has a burn area of 2 m² and a propellant density of 1750 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 5 mm/s?
a) 15.5 kg/s
b) 16.5 kg/s
c) 17.5 kg/s
d) 18.5 kg/s
Answer: c) 17.5 kg/s
16. A liquid propellant rocket has a mixture ratio of 3:1 (oxidizer to fuel). If it consumes 80 kg of fuel
per second, what is the total propellant flow rate?
a) 300 kg/s
b) 310 kg/s
c) 320 kg/s
d) 330 kg/s
Answer: c) 320 kg/s
17. If a hybrid rocket motor has a fuel grain with an initial port diameter of 50 mm and a final port
diameter of 150 mm after burning, what is the average regression rate if the burn time is 30
seconds?
a) 1.33 mm/s
b) 1.67 mm/s
c) 2.00 mm/s
d) 2.33 mm/s
Answer: b) 1.67 mm/s
18. A solid propellant rocket has a propellant mass fraction of 0.85 and a total mass of 10,000 kg.
How much propellant does it contain?
a) 7500 kg
b) 8000 kg
c) 8500 kg
d) 9000 kg
Answer: c) 8500 kg
19. If a liquid propellant rocket engine has a chamber pressure of 5 MPa and a throat area of 0.1 m²,
what is the mass flow rate if the characteristic velocity is 1500 m/s?
a) 323 kg/s
b) 333 kg/s
c) 343 kg/s
d) 353 kg/s
Answer: b) 333 kg/s
20. A hybrid rocket motor uses 70% of its oxidizer in the first 20 seconds of a 50-second burn. If the
total oxidizer mass is 1000 kg, what is the average oxidizer flow rate for the last 30 seconds?
a) 8 kg/s
b) 9 kg/s
c) 10 kg/s
d) 11 kg/s
Answer: c) 10 kg/s
21. If a solid propellant has a density of 1800 kg/m³ and a specific heat of 1500 J/(kg·K), what is its
volumetric heat capacity?
a) 2.5 MJ/(m³·K)
b) 2.7 MJ/(m³·K)
c) 2.9 MJ/(m³·K)
d) 3.1 MJ/(m³·K)
Answer: b) 2.7 MJ/(m³·K)
22. A liquid propellant rocket engine has a thrust of 200 kN and a specific impulse of 320 seconds.
What is its propellant consumption rate?
a) 61.3 kg/s
b) 63.3 kg/s
c) 65.3 kg/s
d) 67.3 kg/s
Answer: b) 63.3 kg/s
23. If a hybrid rocket motor has a regression rate coefficient of 0.5 mm/(s·MPa^0.5) and operates at a
chamber pressure of 4 MPa, what is its regression rate?
a) 0.8 mm/s
b) 1.0 mm/s
c) 1.2 mm/s
d) 1.4 mm/s
Answer: b) 1.0 mm/s
24. A solid rocket booster produces 1.5 MN of thrust for 120 seconds. If its specific impulse is 250
seconds, how much propellant does it consume?
a) 7200 kg
b) 7400 kg
c) 7600 kg
d) 7800 kg
Answer: a) 7200 kg
25. If a liquid propellant rocket has a mixture ratio of 2.2:1 and uses 330 kg of propellant, how much
fuel is used?
a) 101.3 kg
b) 103.1 kg
c) 105.9 kg
d) 107.7 kg
Answer: b) 103.1 kg
26. A rocket engine has a chamber pressure of 10 MPa and an exit pressure of 50 kPa. What is its
pressure ratio?
a) 180
b) 190
c) 200
d) 210
Answer: c) 200
27. If a solid propellant has a density of 1700 kg/m³ and a rocket motor requires 800 kg of propellant,
what volume does the propellant occupy?
a) 0.451 m³
b) 0.461 m³
c) 0.471 m³
d) 0.481 m³
Answer: c) 0.471 m³
28. A liquid hydrogen/liquid oxygen rocket engine has a specific impulse of 450 seconds in vacuum.
What is its exhaust velocity?
a) 4313 m/s
b) 4413 m/s
c) 4513 m/s
d) 4613 m/s
Answer: b) 4413 m/s
29. If a hybrid rocket motor has a regression rate of 1.5 mm/s and burns for 40 seconds, how much of
the solid fuel is consumed (in thickness)?
a) 50 mm
b) 55 mm
c) 60 mm
d) 65 mm
Answer: c) 60 mm
30. A solid rocket motor has a propellant mass of 2000 kg and produces 400 kN of thrust for 30
seconds. What is its specific impulse?
a) 180 seconds
b) 190 seconds
c) 200 seconds
d) 210 seconds
Answer: c) 200 seconds
31. If a liquid propellant rocket engine has a thrust of 150 kN and a specific impulse of 330 seconds,
what is its propellant mass flow rate?
a) 45.5 kg/s
b) 46.5 kg/s
c) 47.5 kg/s
d) 48.5 kg/s
Answer: b) 46.5 kg/s
32. A hybrid rocket uses 75% solid fuel and 25% liquid oxidizer by mass. If the total propellant mass is
600 kg, how much liquid oxidizer is used?
a) 125 kg
b) 135 kg
c) 145 kg
d) 150 kg
Answer: d) 150 kg
33. If a solid propellant has a burning rate of 8 mm/s at a reference pressure of 5 MPa, and the
pressure exponent is 0.3, what is the burning rate at 8 MPa?
a) 9.1 mm/s
b) 9.3 mm/s
c) 9.5 mm/s
d) 9.7 mm/s
Answer: c) 9.5 mm/s
34. A liquid propellant rocket engine has a chamber temperature of 3200 K and a specific heat ratio
of 1.25. If the nozzle expansion ratio is 25, what is the thrust coefficient?
a) 1.75
b) 1.80
c) 1.85
d) 1.90
Answer: b) 1.80
35. If a solid rocket motor has a burn area of 1.5 m² and a propellant density of 1800 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 6 mm/s?
a) 15.5 kg/s
b) 16.2 kg/s
c) 16.9 kg/s
d) 17.6 kg/s
Answer: b) 16.2 kg/s
36. A liquid propellant rocket has a mixture ratio of 2.5:1 (oxidizer to fuel). If it consumes 100 kg of
fuel per second, what is the total propellant flow rate?
a) 330 kg/s
b) 340 kg/s
c) 350 kg/s
d) 360 kg/s
Answer: c) 350 kg/s
37. If a hybrid rocket motor has a fuel grain with an initial port diameter of 40 mm and a final port
diameter of 120 mm after burning, what is the average regression rate if the burn time is 25
seconds?
a) 1.4 mm/s
b) 1.6 mm/s
c) 1.8 mm/s
d) 2.0 mm/s
Answer: b) 1.6 mm/s
38. A solid propellant rocket has a propellant mass fraction of 0.88 and a total mass of 12,000 kg.
How much propellant does it contain?
a) 10,320 kg
b) 10,440 kg
c) 10,560 kg
d) 10,680 kg
Answer: c) 10,560 kg
39. If a liquid propellant rocket engine has a chamber pressure of 6 MPa and a throat area of 0.08 m²,
what is the mass flow rate if the characteristic velocity is 1600 m/s?
a) 290 kg/s
b) 300 kg/s
c) 310 kg/s
d) 320 kg/s
Answer: b) 300 kg/s
40. A hybrid rocket motor uses 60% of its oxidizer in the first 15 seconds of a 40-second burn. If the
total oxidizer mass is 800 kg, what is the average oxidizer flow rate for the last 25 seconds?
a) 11.2 kg/s
b) 12.2 kg/s
c) 12.8 kg/s
d) 13.2 kg/s
Answer: c) 12.8 kg/s
41. If a solid propellant has a density of 1750 kg/m³ and a specific heat of 1400 J/(kg·K), what is its
volumetric heat capacity?
a) 2.35 MJ/(m³·K)
b) 2.45 MJ/(m³·K)
c) 2.55 MJ/(m³·K)
d) 2.65 MJ/(m³·K)
Answer: b) 2.45 MJ/(m³·K)
42. A liquid propellant rocket engine has a thrust of 250 kN and a specific impulse of 340 seconds.
What is its propellant consumption rate?
a) 73.5 kg/s
b) 74.5 kg/s
c) 75.5 kg/s
d) 76.5 kg/s
Answer: c) 75.5 kg/s
A solid rocket motor has a propellant mass of 1000 kg and produces 250 kN of thrust for 40 seconds.
What is its specific impulse?
a) 220 seconds
b) 240 seconds
c) 260 seconds
d) 280 seconds
Answer: b) 240 seconds
11. If a liquid propellant rocket engine has a thrust of 100 kN and a specific impulse of 310 seconds,
what is its propellant mass flow rate?
a) 32.9 kg/s
b) 33.9 kg/s
c) 34.9 kg/s
d) 35.9 kg/s
Answer: a) 32.9 kg/s
12. A hybrid rocket uses 80% solid fuel and 20% liquid oxidizer by mass. If the total propellant mass is
500 kg, how much solid fuel is used?
a) 350 kg
b) 375 kg
c) 400 kg
d) 425 kg
Answer: c) 400 kg
13. If a solid propellant has a burning rate of 10 mm/s at a reference pressure of 7 MPa, and the
pressure exponent is 0.4, what is the burning rate at 10 MPa?
a) 11.5 mm/s
b) 12.0 mm/s
c) 12.5 mm/s
d) 13.0 mm/s
Answer: b) 12.0 mm/s
14. A liquid propellant rocket engine has a chamber temperature of 3500 K and a specific heat ratio
of 1.2. If the nozzle expansion ratio is 20, what is the thrust coefficient?
a) 1.59
b) 1.69
c) 1.79
d) 1.89
Answer: c) 1.79
15. If a solid rocket motor has a burn area of 2 m² and a propellant density of 1750 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 5 mm/s?
a) 15.5 kg/s
b) 16.5 kg/s
c) 17.5 kg/s
d) 18.5 kg/s
Answer: c) 17.5 kg/s
16. A liquid propellant rocket has a mixture ratio of 3:1 (oxidizer to fuel). If it consumes 80 kg of fuel
per second, what is the total propellant flow rate?
a) 300 kg/s
b) 310 kg/s
c) 320 kg/s
d) 330 kg/s
Answer: c) 320 kg/s
17. If a hybrid rocket motor has a fuel grain with an initial port diameter of 50 mm and a final port
diameter of 150 mm after burning, what is the average regression rate if the burn time is 30
seconds?
a) 1.33 mm/s
b) 1.67 mm/s
c) 2.00 mm/s
d) 2.33 mm/s
Answer: b) 1.67 mm/s
18. A solid propellant rocket has a propellant mass fraction of 0.85 and a total mass of 10,000 kg.
How much propellant does it contain?
a) 7500 kg
b) 8000 kg
c) 8500 kg
d) 9000 kg
Answer: c) 8500 kg
19. If a liquid propellant rocket engine has a chamber pressure of 5 MPa and a throat area of 0.1 m²,
what is the mass flow rate if the characteristic velocity is 1500 m/s?
a) 323 kg/s
b) 333 kg/s
c) 343 kg/s
d) 353 kg/s
Answer: b) 333 kg/s
20. A hybrid rocket motor uses 70% of its oxidizer in the first 20 seconds of a 50-second burn. If the
total oxidizer mass is 1000 kg, what is the average oxidizer flow rate for the last 30 seconds?
a) 8 kg/s
b) 9 kg/s
c) 10 kg/s
d) 11 kg/s
Answer: c) 10 kg/s
21. If a solid propellant has a density of 1800 kg/m³ and a specific heat of 1500 J/(kg·K), what is its
volumetric heat capacity?
a) 2.5 MJ/(m³·K)
b) 2.7 MJ/(m³·K)
c) 2.9 MJ/(m³·K)
d) 3.1 MJ/(m³·K)
Answer: b) 2.7 MJ/(m³·K)
22. A liquid propellant rocket engine has a thrust of 200 kN and a specific impulse of 320 seconds.
What is its propellant consumption rate?
a) 61.3 kg/s
b) 63.3 kg/s
c) 65.3 kg/s
d) 67.3 kg/s
Answer: b) 63.3 kg/s
23. If a hybrid rocket motor has a regression rate coefficient of 0.5 mm/(s·MPa^0.5) and operates at a
chamber pressure of 4 MPa, what is its regression rate?
a) 0.8 mm/s
b) 1.0 mm/s
c) 1.2 mm/s
d) 1.4 mm/s
Answer: b) 1.0 mm/s
24. A solid rocket booster produces 1.5 MN of thrust for 120 seconds. If its specific impulse is 250
seconds, how much propellant does it consume?
a) 7200 kg
b) 7400 kg
c) 7600 kg
d) 7800 kg
Answer: a) 7200 kg
25. If a liquid propellant rocket has a mixture ratio of 2.2:1 and uses 330 kg of propellant, how much
fuel is used?
a) 101.3 kg
b) 103.1 kg
c) 105.9 kg
d) 107.7 kg
Answer: b) 103.1 kg
26. A rocket engine has a chamber pressure of 10 MPa and an exit pressure of 50 kPa. What is its
pressure ratio?
a) 180
b) 190
c) 200
d) 210
Answer: c) 200
27. If a solid propellant has a density of 1700 kg/m³ and a rocket motor requires 800 kg of propellant,
what volume does the propellant occupy?
a) 0.451 m³
b) 0.461 m³
c) 0.471 m³
d) 0.481 m³
Answer: c) 0.471 m³
28. A liquid hydrogen/liquid oxygen rocket engine has a specific impulse of 450 seconds in vacuum.
What is its exhaust velocity?
a) 4313 m/s
b) 4413 m/s
c) 4513 m/s
d) 4613 m/s
Answer: b) 4413 m/s
29. If a hybrid rocket motor has a regression rate of 1.5 mm/s and burns for 40 seconds, how much of
the solid fuel is consumed (in thickness)?
a) 50 mm
b) 55 mm
c) 60 mm
d) 65 mm
Answer: c) 60 mm
30. A solid rocket motor has a propellant mass of 2000 kg and produces 400 kN of thrust for 30
seconds. What is its specific impulse?
a) 180 seconds
b) 190 seconds
c) 200 seconds
d) 210 seconds
Answer: c) 200 seconds
31. If a liquid propellant rocket engine has a thrust of 150 kN and a specific impulse of 330 seconds,
what is its propellant mass flow rate?
a) 45.5 kg/s
b) 46.5 kg/s
c) 47.5 kg/s
d) 48.5 kg/s
Answer: b) 46.5 kg/s
32. A hybrid rocket uses 75% solid fuel and 25% liquid oxidizer by mass. If the total propellant mass is
600 kg, how much liquid oxidizer is used?
a) 125 kg
b) 135 kg
c) 145 kg
d) 150 kg
Answer: d) 150 kg
33. If a solid propellant has a burning rate of 8 mm/s at a reference pressure of 5 MPa, and the
pressure exponent is 0.3, what is the burning rate at 8 MPa?
a) 9.1 mm/s
b) 9.3 mm/s
c) 9.5 mm/s
d) 9.7 mm/s
Answer: c) 9.5 mm/s
34. A liquid propellant rocket engine has a chamber temperature of 3200 K and a specific heat ratio
of 1.25. If the nozzle expansion ratio is 25, what is the thrust coefficient?
a) 1.75
b) 1.80
c) 1.85
d) 1.90
Answer: b) 1.80
35. If a solid rocket motor has a burn area of 1.5 m² and a propellant density of 1800 kg/m³, what is
the propellant mass flow rate if the linear burn rate is 6 mm/s?
a) 15.5 kg/s
b) 16.2 kg/s
c) 16.9 kg/s
d) 17.6 kg/s
Answer: b) 16.2 kg/s
36. A liquid propellant rocket has a mixture ratio of 2.5:1 (oxidizer to fuel). If it consumes 100 kg of
fuel per second, what is the total propellant flow rate?
a) 330 kg/s
b) 340 kg/s
c) 350 kg/s
d) 360 kg/s
Answer: c) 350 kg/s
37. If a hybrid rocket motor has a fuel grain with an initial port diameter of 40 mm and a final port
diameter of 120 mm after burning, what is the average regression rate if the burn time is 25
seconds?
a) 1.4 mm/s
b) 1.6 mm/s
c) 1.8 mm/s
d) 2.0 mm/s
Answer: b) 1.6 mm/s
38. A solid propellant rocket has a propellant mass fraction of 0.88 and a total mass of 12,000 kg.
How much propellant does it contain?
a) 10,320 kg
b) 10,440 kg
c) 10,560 kg
d) 10,680 kg
Answer: c) 10,560 kg
39. If a liquid propellant rocket engine has a chamber pressure of 6 MPa and a throat area of 0.08 m²,
what is the mass flow rate if the characteristic velocity is 1600 m/s?
a) 290 kg/s
b) 300 kg/s
c) 310 kg/s
d) 320 kg/s
Answer: b) 300 kg/s
40. A hybrid rocket motor uses 60% of its oxidizer in the first 15 seconds of a 40-second burn. If the
total oxidizer mass is 800 kg, what is the average oxidizer flow rate for the last 25 seconds?
a) 11.2 kg/s
b) 12.2 kg/s
c) 12.8 kg/s
d) 13.2 kg/s
Answer: c) 12.8 kg/s
41. If a solid propellant has a density of 1750 kg/m³ and a specific heat of 1400 J/(kg·K), what is its
volumetric heat capacity?
a) 2.35 MJ/(m³·K)
b) 2.45 MJ/(m³·K)
c) 2.55 MJ/(m³·K)
d) 2.65 MJ/(m³·K)
Answer: b) 2.45 MJ/(m³·K)
42. A liquid propellant rocket engine has a thrust of 250 kN and a specific impulse of 340 seconds.
What is its propellant consumption rate?
a) 73.5 kg/s
b) 74.5 kg/s
c) 75.5 kg/s
d) 76.5 kg/s
Answer: c) 75.5 kg/s
43. If a hybrid rocket motor has a regression rate coefficient of 0.6 mm/(s·MPa^0.5) and operates at a
chamber pressure of 5 MPa, what is its regression rate?
a) 1.2 mm/s
b) 1.3 mm/s
c) 1.4 mm/s
d) 1.5 mm/
