An isolated particle of mass `m` is moving in horizontal plane` xy` along the `x`-axis, at a certain height above the ground. It suddenly explodes into two fragment of masses `m//4` and `3m//4`. An instant later, the smaller fragment is at `y=+15` cm. The larger fragment at this instant is at

Options

A. `y = - 5 cm`
B. `y = +20 cm`
C. `y = + 5cm`
D. `y = -20 cm`

Answer

A

Explanation

As m is moving along X – axis, `V_(cm_y) = 0`
`implies Deltay_(cm) = 0 implies m/4 y_1 + (3m)/4 y_2 = 0 implies y^2 = -(y_1)/3 = - 5cm`