Question

What is the initial velocity of a go-kart traveling at a uniform acceleration of 0.5 m/s^2 for 5s as it slows down to a stop?

Answer 1

The go-kart's velocity
`v` after time
`t` is given by

`v=v_0+at`

where
`v_0` is its initial velocity and
`a` is its acceleration. After
`t=5\,\mathrm s`, the go-kart stops completely, so

`0\,(\mathrm m)/(\mathrm s)=v_0+\left(-0.5\,(\mathrm m)/(\mathrm s^2)\right)(5\,\mathrm s)\implies v_0=2.5\,(\mathrm m)/(\mathrm s)`

where
`a<0` because we know the go-kart is slowing down.