Question

An object travelling at `30m/(sec.)` has kinetic energy `33,750` joules. What is its mass?

Answer 1

Mass of the object is `75` kg.

Explanation:

Energy `E` of an object of mass `m` kg. travelling at `v` `m/(sec.)` is `1/2mv^2` joules.

Hence, mass is given by `(2E)/v^2`

As energy is `33,750` joules and object is traveling at `30` `m/(sec.)`,

its mass is `(33750xx2)/(30xx30)=67500/900=75` kg.