Question

A wave passes from one medium to another medium. Which of the following quantity will change ?

• A. Wavelength
• B. Frequency
• C. Time period
• D. none of these

Answer 1

The correct option is A Wavelength

Sound is propagated in the form of longitudinal waves. When sound travels from one medium to another, both its velocity and wavelength undergo changes. The velocity of sound in a given medium is obtained by the equation $v=f\lambda$, where $f$ is the frequency of sound and $\lambda$ is its wavelength in that medium.

Velocity of sound is directly proportional to the wavelength. Thus, if the velocity of sound doubles when it travels from one medium to another, its wavelength also doubles. The frequency of sound depends upon the source of sound, not the medium of propagation. Hence, it does not change.

Same argument is valid for all waves as well.