A mortar fires a shell of mass M which explodes into two pieces of mass `M/5` and `(4M)/(5)` at the top of the trajectory. The smaller mass falls very close to the mortar. In the same time bigger piece lands a distance D from the mortar. The shell would have fallen at a distance R from the mortar if there was no explosion. The value of D is (neglect air resistance)

Options

A. `(3R)/(2)`
B. `(4R)/(3)`
C. `(5R)/(4)`
D. None of these

Answer

C

Explanation

`x_(CM)=(m_1x_1+m_2x_2)/(m_1+m_2)`
`:. R=((M//5)(0)+(4M//5)D)/(M)`
`:. D=5/4R`