1m long pipe with a movable piston at one end and an opening at the other will be in resonance with a tuning fork vibrating at 340 Hz, if the length of the pipe is 79.3 cm or 25.5 cm. Calculate the speed of sound in air. Neglect the edge effects.

Asked by Pragya Singh | 1 year ago |  140

##### Solution :-

Given,

Frequency of the turning fork, νF = 340 Hz

Length of the pipe, l1 = 0.255 m

As the given pipe is has a piston at one end, it will behave as a pipe with one end closed and the other end open, as depicted in the figure below:

This kind of system creates odd harmonics. We know, fundamental note in a closed pipe is written as:

l1 = $$\dfrac{λ}{2}$$

0.255 x 4 = λ = 1.02m

Therefore speed of sound, v = λvF

= 340 × 1.02 = 346.8 m/s

Answered by Abhisek | 1 year ago

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