Question

A tube closed at one end and containing air produces fundamental note of frequency 256 Hz. If the tube is open at both ends, the fundamental frequency will be ____________.

Options

• 64 Hz

• 128 Hz

• 384 Hz

• 512 Hz

Answer 1

A tube closed at one end and containing air produces fundamental note of frequency 256 Hz. If the tube is open at both ends, the fundamental frequency will be 512 Hz.

Explanation:

For closed pipe,

n = `v/(4l)` = 256 Hz 

`therefore v/l` = 4 × 256    ......(i)

For open pipe,

n' = `v/(2l)`

`therefore v/l` = 2n'          ......(ii)

From (i) and (ii) we get,

2n' = 4 x 256

`therefore  n' =  (4 × 256)/2` = 512 Hz