A mass `M` is suspended from a massless spring. An additional mass `m` stretches the spring further by a distance `x`. The combined mass will oscillate with a period

Options

A. `2pisqrt({((M + m)x)/(mg)})`
B. `2pi sqrt ({(mg)/((M + m)x)})`
C. `2pi sqrt ({((M + m))/(mgx)})`
D. `(pi)/(2) sqrt ({(mg)/((M + m)x)})`

Answer

A

Explanation

`mg = kx rArr :. k = (mg)/(x)`
`T = 2pi sqrt ((M + m)/(R)) = 2pi sqrt(((M + m)x)/(mg))`