Question

A block of mass 4 kg has a linear momentum of magnitude 12 kg m/s. Calculate the kinetic energy of the block.

• A. 3 J
• B. 6 J
• C. 9 J
• D. 18 J
• E. 48 J

Answer 1

The correct option is D 18 J

Here, $m=4kg$ and momentum $p=mv=12$ or $v=12/m=12/4=3m/s$

Thus, the kinetic energy $=\frac{1}{2}m{v}^2=\frac{1}{2}\times 4\times 3^2=18J$