Two open pipes A and B are sounded together such that beats are heard between the first overtone of A and second overtone of B…

Q: Two open pipes A and B are sounded together such that beats are heard between the first overtone of A and second overtone of B. If the fundamental frequency of A and B in 256Hz and 170 Hz respectively, then the beat frequency heard is

(a) 4 Hz

(b) 3 Hz

(c) 2 Hz

(d) 1 Hz

Ans: (c)

Sol: Frequency of first overtone of A is ν_A = 2×256 = 512 Hz

Frequency of second overtone of B is ν_B = 3 × 170 = 510 Hz

Beat Frequency = ν_A – ν_B

= 512 – 510 = 2 Hz