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. `T=2pisqrt(mg//x(M+m))`
B. `T=2pisqrt(((M+m)x//mg))`
C. `T=(pi//2)sqrt((mg//x)(M+m))`
D. `T=2pisqrt(((M+m)//mgx))`

Answer

B

Explanation

`mg=kximpliesk=(mg)/(x)`
`T=2pisqrt((M+m)/(k))=2pisqrt((M+m)/(mg//x))`
`=2pisqrt(((M+m)x)/(mg))`