Question

A ball is thrown horizontally from the top of a building 109 m high. The ball strikes the ground at a point 75 m horizontally away from and below the point of release. What is the speed of the ball just before it strikes the ground? (note: speed is magnitude of velocity at that point).

Answer 1

The speed of the ball just before it strikes the ground is 15.90 m/s.

Step-by-step explanation:

Given that,

Height = 109 m

Distance = 75 m

We need to calculate the time

Using formula for horizontal projectile

`t=\sqrt{(2h)/(g)}`

Where, h = height

Put the value into the formula

`t=\sqrt{(2*109)/(9.8)}`

`t=4.716\ sec`

We need to calculate the speed of the ball just before it strikes the ground

Using formula of speed

`v =(d)/(t)`

Where, v = speed

d = distance

t = time

Put the value into the formula

`v=(75)/(4.716)`

`v=15.90\ m/s`

Hence, The speed of the ball just before it strikes the ground is 15.90 m/s.