Embibe Experts Solutions for Chapter: Sound Waves, Exercise 1: CG PET 2017

A star emitting light of wavelength $5896 \stackrel{\mathrm{o}}{\mathrm{A}}$ is moving away from the earth with a speed of $3600 \mathrm{km}/\mathrm{s}$. The wavelength of the light observed on the earth will

A car, sounding a horn of frequency $1000\mathrm{Hz}$, is moving directly towards a huge wall at a speed of $15 {\mathrm{ms}}^{-1}$. If the speed of sound is $240 {\mathrm{ms}}^{-1}$, then the frequency of echo heard by the driver is

At what speed should a source of sound move, so that staionary observer finds the apparent frequency equal to half of the original frequency?