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 = + cm`
D. `y = -20 cm`

Answer

A

Explanation

`Deltabar(y) = (m_(1)Deltay_(1) + m_(2)Deltay_(2))/(m_(1) + m_(2))`
`rArr 0 = (m)/(4) (15) + (3m)/(4) (y_(2))`
`rArr = y_(2) = -5 cm`