PS Technical Physics

Embry-Riddle Aeronautical University Department of Physical Sciences

Home Work # 6

PS 103 � Technical Physics�I Due Date: October 10, 2014 (Friday)

Name:

Date: October 6, 2014 (Monday)

Semester: Fall-2014

Section:

Total point: 10

Important:

• Home work is due in the beginning of the class on the date mentioned above.

• Please note that providing answers without showing any working will not qualify as correct. So to get full points show EACH AND EVERY STEP.

• To get the full credit make your work readable to grader. It is student’s responsibility to make his/her thought process clear to the grader. Grader will grade whatever is written on the paper.

• Please answer all questions neat and clean in as much detail as you can.

• All the conventions followed in the homework are same as that of lectures.

Question# 1:- Suppose a block with a mass of 3.25 kg is resting on a ramp. If the coe�cient of static friction between the block and ramp is 0.250, what maximum angle can the ramp make with the horizontal before the block starts to slip down?

Question# 2:- The hockey puck, struck by a hockey stick, is given an initial speed of 20.0 m/s on a frozen pond. The puck remains on the ice and slides 1.30⇥102 m, slowing down steadily until it comes to rest. Determine the coe�cient of kinetic friction between the puck and the ice.

Question# 3:- An experimental rocket plane lands on skids on a dry lake bed. If it’s traveling at 80.0 m/s when it touches down, how far does it slide before coming to rest? Assume the coe�cient of kinetic friction between the skids and the lake bed is 0.600.

Question# 4:- An object of mass 2.0 kg starts from rest and slides down an inclined plane 80 cm long in 0.50 s. What net force is acting on the object along the incline?

Question# 5:- An object with mass m1 = 25.00 kg rests on a frictionless horizontal table and is connected to a cable that passes over a pulley and is then fastened to a hanging object with mass m2 = 10.0 kg. Find the acceleration of each object and the tension in the cable.

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Embry-Riddle Aeronautical University

Question# 6:- The coe�cient of static friction between the 3.00 kg crate and the 35.0� incline of Figure 1 is 0.300. What minimum force F must be applied to the crate perpendicular to the incline to prevent the crate from sliding down the incline?

Figure 1: Problem-6

Question# 7:- Find the acceleration reached by each of the two objects shown in Figure 2 if the coe�cient of kinetic friction between the 7.00 kg object and the plane is 0.250.

Figure 2: Problem-7

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