JEE Main 2021 · PhysicsNumerical answerNumerical valueMediumMulti-step

JEE Main 16 March 2021, Shift 2, Physics Q30

Question 30 of 90 in this shift, Physics question 30 of 30, Section B.

A closed organ pipe of length L and an open organ pipe contain gases of densities

\rho_1

and

\rho_2

respectively. The compressibility of gases are equal in both the pipes. Both the pipes are vibrating in their first overtone with same frequency. The length of the open pipe is

\frac{x}{3}L\sqrt{\frac{\rho_1}{\rho_2}}

where

x

is ________. (Round off to the Nearest Integer)

Official answer

NTA final key.

Chapter: Waves
Topic: Resonance in Air Columns
Idea tested: Harmonic Frequency Ratios

Same topic in other shifts

All Resonance in Air Columns questions

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6 Apr 2024, Shift 2 · Q51Two open organ pipes of lengths 60 cm and 90 cm resonate at $6^{\text{th}}$ and $5^{\text{th}}$ harmonics respectively. The difference of…EasyNumerical value
8 Apr 2024, Shift 1 · Q54A closed and an open organ pipe have same lengths. If the ratio of frequencies of their seventh overtones is $\left(\frac{a-1}{a}\right)$ …MediumNumerical value
31 Jan 2024, Shift 1 · Q49The fundamental frequency of a closed organ pipe is equal to the first overtone frequency of an open organ pipe. If length of the open…EasySingle correct
8 Jan 2020, Shift 1 · Q23A one metre long (both ends open) organ pipe is kept in a gas that has double the density of air at STP. Assuming the speed of sound in…MediumNumerical value

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.