9th harmonic of closed pipe =4ℓ19 V14th harmonic of open pipe =ℓ22 V2∴4ℓ19 V1=ℓ22 V2∴4ℓ19ρ1 B=ℓ22ρ2 B⇒ℓ1ℓ2=98ρ2ρ1ℓ2=ℓ1×98×41=920 cm
A closed organ and an open organ tube are filled by two different gases having same bulk modulus but different densities ρ_1 and ρ_2^prime,…
JEE Main 2025 — Physics Waves & Oscillations
2025mcqmedium
A closed organ and an open organ tube are filled by two different gases having same bulk modulus but different densities ρ1 and ρ2′, respectively. The frequency of 9th harmonic of closed tube is identical with 4th harmonic of open tube. If the length of the closed tube is 10 cm and the density ratio of the gases is ρ1:ρ2=1:16, then the length of the open tube is :
Official previous-year question
Held on 22 Jan 2025 · Verified 6 Jul 2026.
Options
- A
715 cm
- B
720 cm
- C
915 cm
- D
920 cm
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