Q

An object moving at 4 m/s has kinetic energy of 120 J. Find its mass.

RRB Group D; RRB Group D 01/10/2018 / Shift-I; 01/10/2018 / Shift-III 2018
✓ Answer: B 15 kg
m = 2K/v² = 240/16 = 15 kg.