Question

If an object with a mass of `3kg` changes speed from `5m/s` to `3m/s`, by how much does its kinetic energy change?

Answer 1

`Delta E_k=-24 J`

Explanation:

`Delta E_k=1/2*m(v_l^2-v_i^2)`
`Delta E_k=1/2*3(3^2-5^2)`
`Delta E_k=1/2 *3(9-25)`
`Delta E_k=1/2*3(-16)`
`Delta E_k=-24 J`