Question

If an object is dropped from rest off a 10.5m high building, how long does it take to hit the ground?

Answer 1

We can calculate the time it takes for the object to hit the ground by using the following equation:

`S=(1)/(2) gt^2`

where S=10.5 m is the initial height of the object,
`g=9.81 m/s^2` is the free-fall acceleration and t is the time. Re-arranging the equation, we can solve for the time:

`t=\sqrt{(2S)/(g)}=\sqrt{(2(10.5 m))/(9.81 m/s^2)}=1.46 s`