Question

If a ball is dropped from rest, what is it’s velocity after 4 seconds

Answer 1

Answer: -39.2 m/s directed downwards

Step-by-step explanation:

We can solve this problem with the following equation:

`V=V_(o)+gt`

Where:

`V` is the ball's velocity at 4 s

`V_(o)=0m/s` is the ball's intial velocity, since it was dropped from rest

`g=-9.8 m/s^(2)` is the acceleration due gravity, aways directed downwards

`t=4 s` is the time

Solving:

`V=0m/s-9.8 m/s^(2)(4 s)`

Finally:

`V=-39.2 m/s` The negative sign indicates the velocity is downwards