An open-ended tube is 7.8 m long. What is the wavelength of a third harmonic standing wave?

1 Answer
Mar 16, 2018

5.2m5.2m

Explanation:

For an open ended tube,at both the ends antinodes are present,so for 11st harmonic it's length ll is equals to distance between two antinodes i.e lambda/2λ2 where, lambdaλ is the wavelength.

So,for 33 rd harmonic l=(3lambda)/2l=3λ2

Or, lambda =(2l)/3λ=2l3

Given, l=7.8ml=7.8m

So,lambda =(2×7.8)/3=5.2mλ=2×7.83=5.2m