Question

A pipe of length 85 cm is closed from one end. Find the number of possible natural oscillations of air colunm in the pipe whose frequencies lie below 1250 Hz. The velocity of sound in air is 340 m/s.

Options

• 12

• 8

• 6

• 4

Answer 1

6

Explanation:

`"Here n'" = ((2"n" - 1)  "v")/(4"L") le 1250`

`therefore ((2"n" - 1) xx 340)/(0.45 xx 4) le 1250`

`therefore 2"n" - 1 le 12.5 Rightarrow "n" le 6.75`

`therefore  "Number of possible oscillations is 6."`