Question

A ball rolls off a horizontal shelf a height h above the floor and takes 0.5s to hit. For the ball to take 1.0s to reach the floor the shelf's height above the floor would have to be___. A) 2h B)3h C) sqrt(2) h D)4h

Answer 1

if rolls off=no initial vertical component of velocity
then S=0t+1/2(9.8)t^2
H1=4.9t1^2
and when t2=2t1 double of 1 is 0.5s
H2=4.9t2^2
=4.9(2t1)^2
=4.9(4t1^2)
=4(4.9t1^2)
=4H1
hope it helps