UPSEE Solved Model Paper 1

For pipe open at both ends, if fundamental frequency = f, then for fundamental vibration of air column,

λ

2

= l
⇒

v

2f

= l
⇒ f =

v

2l

⇒

v

2l

= 240

When pipe is dipped in water for first overtone

3λ

4

=

l

4

⇒

3v

f′

= l
⇒ f' =

3v

l

= 6(

v

2l

) = 6f
= 6 × 240 = 1440Hz