Answer to Question #136631 in Field Theory for lou

Question

An electric car is being driven through a town at 22 m/s. The kinetic energy of the car is 222640 J. Calculate the mass of the car.

Answer 1

The kinetic energy

$${\rm KE}=\frac{mv^2}{2}$$

Hence, the mass of a car

$$m=\frac{2{\rm KE}}{v^2}=\rm\frac{2\times 222640\: J}{(22\: m/s)^2}=920\: kg$$