Question

12. An organ pipe that is 1.75 m long and open at both ends produces sound of

frequency 303 Hz when resonating in its second overtone. What is the speed of

sound in the room?

295 m/s

328 m/s

354 m/s

389 m/s

401 m/s

Answer 1

354 m/s

Step-by-step explanation:

For the second overtune (Third harmonic) of an open pipe,

λ = 2L/3................................ Equation 1

Where L = Length of the open pipe, λ = Wave length.

Given: L = 1.75 m.

Substitute into equation 1

λ = 2(1.75)/3

λ = 1.17 m.

From the question,

V = λf.......................... Equation 2

V = speed of sound in the room, f = frequency

Given: f = 303 Hz.

Substitute into equation 2

V = 1.17(303)

V = 353.5

V ≈ 354 m/s

Hence the right answer is 354 m/s