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1.pptxPROJECTILE MOTION
Statics & Dynamics
Raad Alharthi
Sanad Alotaibi
Dr.Roopaei Mehdi
Projectile
Any object which projected by some means and continues to move due to its own inertia (mass).
Projectile Motion
Motion in which an object moves along a curved path under the action of gravity.
Parabolic trajectory
Projectile moves in 2- dimensions:
Vertical Motion (Gravity)
Horizontal Motion (No gravity)
Examples of projectile motion
Projectile Motion
Vertical and Horizontal motion are independent of each other
Horizontal motion has no external forces
No acceleration
Constant velocity
Vertical Motion is affected by gravity
Acceleration =Gravity
Velocity is not constant
Resultant velocity is obtained from the horizontal and vertical component
Equations
Horizontal Motion
Velocity:
Displacement:
Vertical Motion
Velocity:
Displacement:
Variables affecting the trajectory
Initial Velocity
Angle
Another Equations
By rearranging the previous equation, the following can be derived:
Special case: Horizontally launched projectile
NO upward trajectory and NO initial VERTICAL velocity.
Example 1
A place kicker kicks a football with a velocity of 20 m/s and angle of 53 degrees.
How long the ball is in the air?
How far away does it land?
How high does it travel?
Example 1
How long the ball is in the air?
When the ball touches the ground y=0. then
Example 1
2. How far away does it land?
3. How high does it travel?
As the trajectory is a parabola, the maximum height is reached at the middle of the trajectory. This means, that the maximum height is reached at t=3.26/2=1.63. Then:
Example 2
Dividing eqn .(2) by eqn. (1):
Vertical motion:
(1)
(2)
Horizontal motion:
Substituting in eqn(1)
References
Hibbeler, R. C., & Schiavone, P. (2004). Engineering mechanics: Statics and dynamics (10th ed.). Upper Saddle River: Pearson/Prentice Hall.
bowlesphysics.com/images/AP_Physics_B_-_Projectile_Motion.ppt
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