Question

An moving object has kinetic energy K E = 100 J and momentum p = 50 kg m/s. What is its mass?

• A. 2 kg
• B. 4 kg
• C. 6.25 kg
• D. 12.5 kg
• E. 25 kg

Answer 1

The correct option is D 12.5 kg

Given : $K.E=100$ J $p=50$ kg m/s

Using $K.E=\frac{p^2}{2m}$

$\therefore$ $100=\frac{{50}^2}{2m}$ $⟹m=12.5$ kg