Speed of Sound in Various Mediums

→ Speed of sound depends on the nature of material through which it travels. It is slowest in gases,

faster in liquids and fastest in solids.

→ Speed of sound increases with the rise in temperature.

→ Speed of sound increases as humidity of air increases.

→ Speed of light is faster than speed of sound.

→ In air, speed of sound is 344 ms-1 at 22ºC.

 Sonic Boom

→ Some aircrafts, bullets, rockets etc. have ‘supersonic speed’.

• Supersonic refers to the speed of an object which is greater than the speed of sound and it

produces extremely loud sound waves called ‘shock waves’ in air.


 Reflection of Sound

→ Like light, sound also bounce back when it falls on a hard surface. It is called reflection of sound.

• The laws of reflection of light are obeyed during reflection of sound.

(i) The incident sound wave, the reflected sound wave and normal at the point of incidence lie

same plane.

(ii) Angle of reflection of sound is always equal to the angle of incidence of sound.