Physics (NTSE/Olympiad)  

5. Sound

Reflection of Sound

Sound waves like light waves also get reflected from plane and spherical surfaces. During reflection, sound waves obey the laws of reflections. The reflection of sound from a hard surface can be observed by performing a simple experiment on the equipment as shown in fig.

Reflection of sound from a hard surface
Sound waves have much longer wavelength than the light waves. Therefore unlike light waves, sound waves do not need smooth surfaces for suffering reflection. That is why, a brick wall, a wooden board, a row of trees, a hill etc. serve as the reflectors of sound waves.
To have an appreciable reflection of sound waves from any surface, it should have dimensions equal or larger than the wavelength of the sound waves falling on it. That is, a smaller object will not reflect the sound waves of larger wavelength.


NTSE Physics (Class X)

NTSE Physics (Class IX)


NTSE Physics Course (Class 9 & 10)

NTSE Chemistry Course (Class 9 & 10)

NTSE Geography Course (Class 9 & 10)

NTSE Biology Course (Class 9 & 10)

NTSE Democratic Politics Course (Class 9 & 10)

NTSE Economics Course (Class 9 & 10)

NTSE History Course (Class 9 & 10)

NTSE Mathematics Course (Class 9 & 10)