Question

If length of a closed organ pipe is 60 cm and velocity of sound is 360 m/s, then the frequency of 1^st overtone is ____________.

Options

• 150 Hz

• 450 Hz

• 900 Hz

• 180 Hz

Answer 1

If length of a closed organ pipe is 60 cm and velocity of sound is 360 m/s, then the frequency of 1^st overtone is 450 Hz.

Explanation:

For closed organ pipe,

`l = lambda/4`

`therefore  lambda/4 = 60 xx 10^-2 = 0.6`

`therefore  lambda = 2.4  "m"`

`"Frequency n" = "v"/lambda = 360/2.4 = 150`

`therefore  "First overtone of closed organ pipe is, 3n = 3(150) = 450 Hz"`