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.

Applications of Reflection of Sound

(i) Megaphone, loudspeakers, bulb horns and trumpets, shehnai etc. are designed to send sound to

a particular direction without spreading all around.

→ All these instruments have funnel tube which reflects sound waves repeatedly towards audio

In this amplitude of sound waves adds up to increase loudness of sound.

(ii) Stethoscope: It is a medical instrument used for listening the sounds produced in human bo

mainly in heart and lungs. The sound of the heartbeats reaches the doctor’s ears by the multipe

reflection of the sound waves in the rubber tube of stethoscope.


(iii) Sound Board: In big halls or auditoriums sound is absorbed by walls, ceiling, seats etc. So a

curved board (sound board) is placed behind the speakers so that his speech can be heard easily

by audiences. The soundboard works on the multiple reflection of sound.


(iv) The ceiling of concert halls are made curved, so that sound after reflection from ceiling, rea

all the parts of the hall.