Question

A tuning fork sends sounds waves in air. If the temperature of air increases which of the following parameters will change?

• A. amplitude
• B. frequency
• C. wave length
• D. time- period

Answer 1

Answer: (C)

If temperature $T$ increases , speed of sound $v$ also increases ,

now by , $\lambda =v/f$ , as $v$ increases , $\lambda$ (wavelength) will increase .

Frequency is characterised by the source of sound hence it is not affected by temperature , and as $T=1/f$ , so time period also doesn't change .

Amplitude depends upon the energy given to the fork , therefore unaffected by the temperature change .