Reflection of Sound

(i) How do bats use ultrasound to catch prey?
(ii) Describe the working and an application of the SONAR.

(i). Does sound follow the same law of reflection as light? Explain.
(ii). List two practical applications for sound wave reflection.
(iii). 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, (i).(i).$g=10{\mathrm{ms}}^{-2}$ and speed of sound is $340{\mathrm{ms}}^{-1}$.

Explain in detail about sonography.

Sonography is an application of infrared waves.

What do you mean by sonography? Which waves are being used in that?

Which type of wave is used in sonography?

Select bad reflectors of sound from the following:

Hard, thick, firm materials are usually good reflectors of sound.

Brick is a bad reflector of sound.

Name some good and bad reflectors of light.

N in SONAR stands for _____.

A reflection of sound, arriving at the listener in less than $0.1 \mathrm{s}$ after the direct sound is called _____.

A reflection of sound, arriving at the listener in less than $0.1 \mathrm{s}$ after the direct sound is called _____.

The minimum distance required to hear a distinct echo from the source of sound is _____ $(17.2 / 20.1)$ metre.

At 20^o C, the minimum distance of a person from a sound reflecting surface to hear an echo is
 

 Practical applications of reflection of sound waves are:
 

Select the uses of multiple reflections of sound. 

What is the multiple reflection of sound known as when it persists in a place even after the source of sound has stopped? 
(Choose from: Echo, Reverberation,Vibration)

How will you reduce reverberations in public halls or buildings?

Echoes are caused by the ____________ of sound.