Question

A car moving with a velocity of 20 meters/second has 1.8**10^5 joules of kinetic energy what is the mass of the car?

Answer 1

Kinetic energy = 1/2 x mass x velocity^2

mass = kinetic energy x 2 / velocity ^2

mass = (1.8 x 10^5) x 2/ 20^2

mass = 900 kg.