The fundamental frequency in an open organ pipe is equal to the third harmonic of a closed organ pip

Q: What is NEET?

NEET is a competitive examination conducted in India. This question is from the 2018 NEET Physics paper.

Q: How can I prepare for NEET Physics?

To prepare for NEET Physics, practice previous year questions (PYQs), understand concepts thoroughly, and solve mock tests regularly. This 2018 question covers Waves topic.

Q: What is the difficulty level of this question?

This NEET 2018 Physics question has a easy difficulty level and is marked as an important question.

Q: Where can I find more NEET previous year questions?

You can find more NEET previous year questions on AspirantMitraa. Browse by subject, topic, year, and difficulty level to practice effectively.

Question

The fundamental frequency in an open organ pipe is equal to the third harmonic of a closed organ pipe. If the length of the closed organ pipe is 20 cm, the length of the open organ pipe is

Accepted Answer

Correct Answer: A — 13.2 cmStep-by-step Solution:For a closed organ pipe (closed at one end):Harmonics allowed: 1st (fundamental), 3rd, 5th,... (only odd harmonics)Third harmonic frequency: f_closed = 3v/(4L_c) = 3v/(4 × 20) = 3v/80For an open organ pipe (open at both ends):Fundamental frequency: f_open = v/(2L_o)Given: f_open = f_closed (third harmonic)v/(2L_o) = 3v/802L_o = 80/3L_o = 40/3 ≈ 13.3 cm ≈ 13.2 cmWhy other options are incorrect:Option B (8 cm): Would give f_open = v/16, while f_closed (3rd harmonic) = 3v/80; these are not equal. Option C (16 cm): f_open = v/32, not equal to 3v/80. Option D (12.5 cm): f_open = v/25 ≠ 3v/80.Key Concept: Closed organ pipe: only odd harmonics, f_n = (2n-1)v/(4L), n = 1, 2, 3... Open organ pipe: all harmonics, f_n = nv/(2L), n = 1, 2, 3... Fundamental of open pipe = f₁ = v/(2L).

The fundamental frequency in an open organ pipe is equal to the third harmonic of a closed organ pipe. If the length of the closed organ pipe is 20 cm, the length of the open organ pipe is

Master NEET with Our Test Series

More Questions from Waves

Frequently Asked Questions

The fundamental frequency in an open organ pipe is equal to the third harmonic of a closed organ pipe. If the length of the closed organ pipe is 20 cm, the length of the open organ pipe is

Master NEET with Our Test Series

More Questions from Waves

Frequently Asked Questions