A sonometer wire vibrates with frequency `n_1` in air under suitable load of specific gravity `sigma` . When the load is immersed in water , the frequency of vibration of wire `n_2` will be …..

Options

A. `n_1sqrt((sigma+1)/(sigma))`
B. `n_1sqrt((sigma-1)/(sigma))`
C. `n_1sqrt((sigma)/(sigma+1))`
D. `n_1sqrt((sigma)/(sigma-1))`

Answer

B

Explanation

`n_2/n_1 = sqrt(T_2/T_1)`
`T_1-T_2` = loss of weight = mg
`T_2-T_1 - mg = (sigma - 1) Vg`
`therefore n_2/n_1 = sqrt(((sigma-1)Vg)/(sigmaVg))`
`therefore n_2=n_1 sqrt((sigma-1)/(sigma))`