A mass of `1 kg` attached to the bottom of a spring has a certain frequency of vibration. The following mass has to be added to it in order to reduce the frequency by half :

Options

A. `1 kg`
B. `2 kg`
C. `3 kg`
D. `4 kg`

Answer

C

Explanation

`f_(1) = (1)/(2pi)sqrt((K)/(m_(1)))`
`f_(2) = (1)/(2pi)sqrt((K)/(m_(2)))`
`f_(2) = (f_(1))/(2)` or `m_(2) = 4m_(1)` or `m_(2) - m_(1) = kg`