Answer: 600 Hz.
- A 400 Hz
- B 600 Hz
- C 200 Hz
- D 800 Hz
Correct answer: B. 600 Hz
Explanation: For an open pipe overtones are 2f, 3f, ...; the second overtone is the 3rd harmonic = 3·200 = 600 Hz.
A standing wave forms from two identical waves travelling in opposite directions and interfering; nodes (always zero displacement) and antinodes (maximum displacement) stay fixed in place, unlike a travelling wave where the whole pattern moves.
Concept context
Wave types, superposition, standing waves, Doppler effect, and sound intensity.