Heena Sharma, Shubhankat Vats and, Rashmi Gupta Solutions for Chapter: Sound, Exercise 6: Challengers*

A radar signal is reflected by an aeroplane and is received in $2\times {10}^{-5} \mathrm{s}$ after it was sent. If the speed of these waves is $3\times {10}^8 \mathrm{m} {\mathrm{s}}^{-1}$ how far is the aeroplane?

A disused railway line has a length of $300 \mathrm{m}$ . A man puts his ear against one end of the rail and another man hits the other end with a metal hammer. Sound travels at $5000 \mathrm{m} {\mathrm{s}}^{-1}$ in steel. The time it takes for the sound to travel along the rail is:

A sound produce in air cannot be heard by a person deep inside the water. This is because :

A man stands at one end of a long steel pipe hits it with a hammer. Another man standing at the other end of the pipe hear $2$ seconds. This is because :

The value of $x$ in the given figure for hearing the loudest ticking sound is

A lighting flash was seen on the sky $10 \mathrm{s}$ before the thunder sound. How far was the cloud?
Speed of sound is $340 \mathrm{m} {\mathrm{s}}^{-1}$.

A stone is dropped from the top of a tower $500 \mathrm{m}$ high into a pond of water at the base of the tower. When is the splash heard at the top? Given, $g=10 \mathrm{m} {\mathrm{s}}^{-2}$ and speed of sound $v=340 \mathrm{m} {\mathrm{s}}^{-1}$.

A boy hears the echo of his own voice from a distance hill after $0.8 \mathrm{second}.$ If the speed of sound in air is $340 \mathrm{m} {\mathrm{s}}^{-1}$.