A load of mass `M` is attached to the bottom of a spring of mass `'M //3'` and spring constant 'K'. If the system is set into oscillation, the time period of oscillation is

Options

A. M
B. 2 M
C. 3 M
D. 4 M

Answer

C

Explanation

`T=2pisqrt((M)/(K))`
`2T=2pisqrt((M+m)/(K))`
`(1)/(2)=2pisqrt((M)/(M+m))therefore (1)/(4)=(M)/(M+m)`
`m=3M`