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Two open organ pipes of lengths 60 cm and 90 cm resonate at 6th and 5th harmonics respectively. The difference of frequencies for the given modes is Hz. (Velocity of sound in air = 333 m/s)
740
Open pipe: fn = nv2L ( antinodes at both ends, all harmonics present)
f6 = 6 3332 0.6 = 1665 Hz
f5 = 5 3332 0.9 = 925 Hz
= 1665 - 925 = 740 Hz
Answer: 740
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