Find the natural frequency of the system shown in figure. The pulleys are smooth and massless.

Answer

A, B

Explanation

If the mass `M` is displaced by `x` from its mean position each spring further streches by `2x`.

Net restoring force `F = - 8kx`
`:. M.a = - 8kx`
`f = (1)/(2pi) sqrt|(a)/(x)|`
`= (1)/(2pi) sqrt((8k)/(M))`
`= (1)/(p)i sqrt ((2k)/(M))`