Question

The velocity of sound in open ended tube in 330m/s, the frequency of a wave is 1.1 kHz and length of the tube is 30cm, then number of harmonics that it will emit is?

(a) 2

(b) 3

(c) 4

(d) 5

I have been asked this question in class test.

I need to ask this question from Travelling Waves in chapter Waves of Engineering Physics I

Answer 1

The correct answer is (a) 2

Explanation: For an open tube,

vn=nv/2L

1.1×10^3=(n×330)/(2×0.30)

n=2.