According to question, tuning fork gives 1 beat/second with (N) 3rd normal mode. Therefore, organ pipe will have frequency (256±1)Hz. In open organ pipe, frequency n=2ℓNV or, 255=2×ℓ3×340⇒ℓ=2 m=200 cm
A tuning fork vibrates with frequency 256 ~Hz and gives one best per second with the third normal mode of vibration of an open pipe. What is the…
JEE Main 2018 — Physics Waves & Oscillations
2018mcqeasy
A tuning fork vibrates with frequency 256 Hz and gives one best per second with the third normal mode of vibration of an open pipe. What is the length of the pipe? (Speed of sound of air is 340 ms−1 )
Official previous-year question
Held on 15 Apr 2018 · Verified 6 Jul 2026.
Options
- A
(a) 190 cm
- B
180 cm
- C
220 cm
- D
200 cm
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