Question

A tube, closed at one end and containing air, produces, when excited, the fundamental note of frequency 512 Hz. If the tube is opened at both ends what is the fundamental frequency that can be excited (in Hz)? 

(A) 256 

(B) 1024 

(C) 128 

(D) 512

Answer 1

The correct option is  (B) 1024.

Explanation:

When tube is close, f_o = {V / 4ℓ} = 512 Hz 

When tube is opened at both the end, f_o' = (V / 2ℓ) 

∴ f_o' = 2 f_o 

= 2 × 512 

= 1024 Hz