A train whistle produces a continuous sound whose time period is measured to be .

PHYSICS · Multi-part · CBSE · Physics · Waves · Waves

Problem

A train whistle produces a continuous sound whose time period is measured to be

0.004\,\text{s}

. (i) Show that the wavelength

\lambda

of any wave can be expressed in terms of its speed

v

and its time period

T

. (ii) At

15^{\circ}\text{C}

, the speed of sound in air is

340\,\text{m\!/s}

. Calculate the wavelength of the whistle’s sound in air at this temperature. (iii) The speed of sound increases by about

0.6\,\text{m\!/s}

for every

1^{\circ}\text{C}

rise in temperature. Determine the wavelength of the same sound at

30^{\circ}\text{C}

, assuming its frequency remains unchanged.