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

distance in a minute=0.5 times 30=15 meters
distance in a second=15 divided by 60=0.25 meters per second
hope it helps

Answer 2

For the ball to take 1.0 s to reach the floor the shelf's height above the floor would have to be 4 h.

Step-by-step explanation:

According to second equation of motion, the height or the distance covered by an object is given by :

`s=ut+(1)/(2)at^2`

Since, the ball rolls so the initial vertical component of velocity will be equal to 0. From above equation it is clear that,

`h\propto t^2`

Let h be the height above the floor when the ball taken 0.5 s to hit. At 1 s the ball is H height above the floor.

So,
`(h)/(H)=(kt_1^2)/(kt_2^2)`

`(h)/(H)=(0.5^2)/(1^2)`

After solving, H = 4 h

Hence, for the ball to take 1.0 s to reach the floor the shelf's height above the floor would have to be 4 h.