Sound Needs a Medium for Propagation

Sound travels faster in _____ air.

Sound cannot be heard by us when it is produced by a 

Sound cannot travel through a -

Sound can travel through

State the factors on which the speed of sound depends.

A source of wave produces 40 crests and 40 troughs in 0.4 seconds, then the frequency of the wave is

If 20 waves are produced per second, then its frequency in Hz is

When a vibrating object moves forward, it pushes the air in front of it creating a region of high pressure. This phenomenon is called_____.

A baby recognizes her mother by her voice. Name the characteristic of sound involved.

In which medium does sound travel faster?

How does sound transmit in solids, liquids and gases? Explain it.

Speed of sound at$0°\mathrm{C}$ in air is

Sound will travel slower through an iron bar than an atmosphere of nitrogen.

Sound can travel in vacuum also.

Sound can travel only in vacuum.

Sound cannot travel in _____.

In which medium sound travels the lowest?

Can sound travel through vacuum?