Two children are playing a game in which they try to hit a small box using a spring loaded machine gun, which is fixed rigidly to a table at a height `h` above the top of the box. The spring has spring constant `k` and the box is at a horizontal distance `l` from `O`. The first child compresses the spring a distanc `x_(0)` and find that the marble falls short of box by a horizontal distance `y`. The second child compreses the spring by an extra amount `Deltax` so that marble lands in the box. The value of `Deltax` is

Options

A. `lsqrt((mg)/(hk))`
B. `lsqrt((2mg)/(hk))`
C. `2ysqrt((mg)/(hk))`
D. `ysqrt((mg)/(2hk))`

Answer

D