Question

If an object with a mass of `12 kg` changes speed from `1 m/s` to `2 m/s`, by how much does its kinetic energy change?

Answer 1

The kinetic energy increases by `6"J"`

Explanation:

The expression for kinetic energy is :

`KE=1/2mv^2`

The initial `KE` is :

`1/2xx12xx1=6"J"`

After the increase in speed this becomes:

`1/2xx12xx2=12"J"`

So you can see that the `KE` has increased from 6 to 12J which is an increase in 6J.