Question

A resonance air column of length $40\,\,cm$ resonates with a tuning fork of frequency $450\,\,Hz$ . Ignoring end correction, the velocity of sound in air will be:

• A. $1020\,\,m/s$
• B. $920\,\,m/s$
• C. $820\,\,m/s$
• D. $720\,\,m/s$

Answer 1

Answer: (D)

$720\,\,m/s$

Answer 2

Here: length of column $=40\,\,cm=0.4\,\,m$ Frequency of tuning fork $=450\,Hz$ Using the formula $n=\frac{v}{4l}$ or $v=450\times 4\times 0.4=720\,\,m/s$