Projectile Motion-Additional Practice

Remember: a_y=-9.8 m/s², a_x=0 m/s²,

d_y max at middle of path, v_y at middle of path=0

if v_i is all horizontal, then v_ix=v_fx since a_x=0 m/s²

t_x=t_y

Football Problem: Show all work and diagram below.

A place kicker kicks a football at an angle of θ = 40^o above the horizontal. The initial speed of the ball is 22 m/s.

a) Ignore air resistance and find the maximum height that the ball attains. (10 m)

b) The total time that the ball is in the air. (2.9 s)

c) The range of the kickoff. (49 m)

A Falling Care Package from a Plane Problem: Show all work and diagram below.

An airplane is moving horizontally with a constant velocity of 115 m/s at an altitude of 1050 m. The plane releases a “care package” that falls to the ground along a curved trajectory.

a) Ignore air resistance and determine the time required for the package to hit the ground. (14.6 s)

b) Find the speed of the package and the angle (direction) or the velocity vector just before the package hits the ground. (v_fy=-143 m/s, v_fx=115 m/s, v_f=184 m/s at 51^o below the horizontal)