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 $n=\frac{v}{4 l}$
or $v=450 \times 4 \times 0.4$
$=720\, m / s$