Question

Two sounds having wavelengths $1.3m$ and $3.9m$ have the same speed in a medium. A person listens to these sounds. What difference would the listener feel?

• A. First sound is heard with better quality.
• B. First sound is louder.
• C. First sound is heard with higher pitch.
• D. Second sound is heard with higher pitch.

Answer 1

The correct option is C First sound is heard with higher pitch.

Speed (v) of the wave is the product of frequency (f) and wavelength ($\lambda$),
$f_1=\frac{v}{{\lambda }_1}$
$f_2=\frac{v}{{\lambda }_2}$

$\frac{f_1}{f_2}=\frac{v/1.3}{v/3.9}=3$

As $f_1$ is $3$ times greater than $f_2$, first sound has higher pitch than the second one, because higher the frequency, higher is the pitch.

The loudness of the sound depends on amplitude and the quality of the sound depends on the shape of the wave form.