2023 WavesStanding Waves in Organ Pipes Easy Question 5 of 59 in Waves

The ratio of frequencies of fundamental harmonic produced by an open pipe to that of a closed pipe having the same length is

A $3:1$
B $1:2$
C $2:1$
D $1:3$

The answer is C.

Solution

Open pipe: $\frac{v}{2L}$; closed pipe: $\frac{v}{4L}$; ratio $2:1$.

Fundamental harmonic frequency of open pipe $=\frac{v}{2L}=v_1$ (say) Fundamental harmonic frequency of closed pipe $=\frac{v}{4L}=v_2$ (say) $\Rightarrow\frac{v_1}{v_2}=\frac{v/2L}{v/4L}=2:1$

Concept open vs closed pipe fundamental

Waves in past papers

59 questions from this chapter have appeared across 25 exam years.