Q.

In the experiment for the determination of the speed of sound in air using the resonance column method, the length of the air column that resonates in the fundamental mode, with a tuning fork is 0.1 m. When this length is changed to 0.35 m, the same tuning fork resonates with the first overtone. Calculate the end correction.              [2003]

1 0.012 m  
2 0.025 m  
3 0.05 m  
4 0.024 m  

Ans.

(2)

Let x be the end correction.

1+x=λ4    or,    λ=4(1+x)

(2+x)=3λ4    or    λ=43(2+x)

  ν1=vλ1=v4(1+x)

  ν2=vλ2=3v4(2+x)

Given ν1=ν2

  v4(1+x)=3v4(2+x)

or,  x=0.025 m