Question

If an object with a mass of `5 kg` changes speed from `3m/s` to `16 m/s`, by how much does its kinetic energy change?

Answer 1

`Delta E=617.5" Joules"`

Explanation:

`m:"mass"`

`v_i:"initial velocity"`

`v_f:"final velocity"`

`E_1=1/2m*v_i^2`

`E_2=1/2*m*v_f^2`

`Delta E=E_2-E_1`

`Delta E=1/2*m-v_f^2-1/2*m*v_i^2`

`Delta E=1/2*m(v_f^2-v_i^2)`

`Delta E=1/2*5*(16^2-3^2)`

`Delta E=5/2(256-9)`

`Delta E=5/2*247`

`Delta E=617.5 " Joules"`