Two balls are simultaneously rolled off a flat tabletop which is 1m above the fl
ID: 1489349 • Letter: T
Question
Two balls are simultaneously rolled off a flat tabletop which is 1m above the floor. Ball A has a horizontal velocity of 2m/s while Ball B has horizontal velocity of 6m/s. Both balls are rolled off at exactly the same time.
A: Which Ball hits the ground first?
B: Which ball is going faster when it hits the ground?
C: Which ball has a higher acceleration in the air?
D: How long before ball A hits the ground?
E: How far does ball A travel horizontally before it hits the ground?
F: What was ball A's speed when it hits the ground?
Explanation / Answer
A) Both balls hit the ground at the same time.
B) Ball B
C) Both balls will have same acceleration
D) let t is the time taken
use, h = voy*t + 0.5*g*t^2
h = 0 + 0.5*g*t^2
==> t = sqrt(2*h/g)
= sqrt(2*1/9.8)
= 0.4518 s
E) xA = vox*t
= 2*0.4518
= 0.9036 m
F) vx = vox = 2 m/s
vy = voy + g*t
= 0 + 9.8*0.4518
= 4.43 m/s
so, v = sqrt(vx^2 +vy^2)
= sqrt(2^2 + 4.43^2)
= 4.86 m/s