(a) Mention two practical applications of reflection of sound waves.

(b) How is the pressure variation in a sound wave amplified in human ear ?

© In a ripple tank, ten ripples are produced per second. If the distance between a trough and a neighbouring crest is 12 cm, calculate the frequency, wavelength and velocity of the wave.

# (a) Mention two practical applications of reflection of sound waves. (b) How is the pressure variation in a sound wave amplified in human ear?

**prasanna**#1

**prasanna**#2

(a) Megaphone, stethoscope.

(b) The pressure variation in the human ear is amplified by three bones anvil, hammer, stirrup.

© Frequency =10 Hertz.

Distance between adjacent crest and trough = 12 cm.

Wavelength = Distance between adjacent crests = 12 + 12 = 24 cm.

Velocity = Wavelength x Frequency = 24 x 10 = 240 cm s^-1.