## Question

A stone hangs from the free end of a sonometer wire whose vibrating length, when tuned to a tuning fork, is 40 cm. When the stone hangs wholly immersed in water, the resonant length is reduced to 30 cm. The relative density of the stone is

### Solution

16/7

where *M* = mass of stone. If ρ is the density of the stone and*V* its volume, then *m* = ρ *V*. When the stone is wholly immersed in water of density ρ*’*, the effective weight of the stone

Given *l* = 40 cm and *l’* = 30 cm. Also *V* = *V’*, which gives

#### SIMILAR QUESTIONS

Transverse wave of amplitude 10 cm is generated at one end (*x* = 0) of a long string by a tuning fork of frequency 500 Hz. At a certain instant of time, the displacement of a particle *A* at *x* = 100 cm is – 5 cm and of particle *B* at *x* = 200 cm is +5 cm. What is the wavelength of the wave?

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Figure shows the shape of part of a long string in which transverse waves are produced by attaching one end of the string to tuning fork of frequency 250 Hz. What is the velocity of the waves?

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