A sonometer wire resonates with a given tuning fork forming a standing wave with five antinodes between the two bridges when a mass of `9 kg` is suspended from the wire. When this mass is replaced by a mass 'M' kg, the wire resonates with the same tuning fork forming three antinodes for the same positions of the bridges. Find the value of `M`.

Options

A. 25 kg
B. 5 kg
C. 12.5 kg
D. `1//25 kg`

Answer

A

Explanation

`f_0=5/(2l) sqrt((9g)/mu)=3/(2l) sqrt((mg)/mu) implies M=25 kg`