Question

When you speak to your friend which of the following quantities have a unique value in the sound produced by both the boys?

• A. amplitude
• B. wave velocity
• C. frequency
• D. wavelength

Answer 1

Answer: (B)

wave velocity

Out of the given quantities , wave velocity has a unique value . Because both the friends are producing the sound in the same medium , and wave velocity depends upon medium , which is not changing here .

Amplitude of the sounds depends upon the energy given by any of the friends to sound , so it may change .

Frequency of sound depends upon the thickness of vocal cords of two friends , so it also may vary . Now wavelength $\lambda \propto 1/f$, for a constant velocity , when frequency $f$ changes , wavelength will also change .