Question

An electrically maintained tuning fork vibrates with constant frequency and constant amplitude. If the temperature of the surrounding air increases but pressure remains constant, the produced will have
(a) larger wavelength
(b) larger frequency
(c) larger velocity
(d) larger time period.

Answer 1

(a) larger wavelength
(c) larger velocity

The velocity varies with temperature as $v\propto \sqrt{T}$. Therefore, it increases.
Since the frequency remains constant, the wavelength will increase as $\lambda \propto v$.