Question

When the pitch of the note produced by a harmonium is lowered, then the wavelength of the note will be:
A. Decreases
B. First decreases then increases
C. Increases
D. Remains the same

Answer 1

Hint:In sound waves, Pitch is defined as how much sound is high or how much sound is low, this highness or lowness of sound is measured and it’s called pitch of the sound. And wavelength is the measurement of between two successive crests and trough of the wave.

Complete answer:
 In sound waves, as we know that frequency of the wave is inversely proportional to the wavelength of the wave. If we increase the wavelength of the wave its frequency decreases.And, the pitch of the sound wave is directly proportional to the frequency of the sound wave.

In the given question we have, Pitch of the harmonium is lowered, hence the frequency of the sound wave also gets decreased as both quantities are directly proportional to each other. As frequency gets decreased of the harmonium its wavelength will get increased as both physical quantities are inversely proportional to each other.

Hence, the correct option is C.

Note:In mathematical formulation the wavelength of the sound wave and frequency of the sound wave are related with velocity of sound wave as $\text{speed} = \lambda\, \nu $.And a sound which is produced with multiple frequencies is called a note such as a note produced by a harmonium or musical notes.