In a resonance column experiment, a tuning fork of frequency 400 Hz is used. The first resonance is observed when the air column has a length of 20.0 cm and the second resonance is observed when the air column has a length of 62.0 cm. (a) Find the speed of sound in air.(b) How much distance above the open end does the pressure node form ?

Answer

A, B, C

Explanation

Here given `I_2=0.67m, `
`I_1=0.2m, f=400Hz`
we know that
`lamda=2(I_2-I_1)`
`rarr lamda=2(62-60)=84cm=0.84m`
`rarrv=nlamda=0.84xx400=336m/s`
we know from above that
`I_1=d=lamda/4`
`rarr d=lamda/4`
`I_1=21-20=1cm`