Practice Questions:

Example 1: A typical sound wave traveling at 360 m/s has a frequency of 1200 Hz. Find its wavelength.

Solution:

ν� = 1200 Hz, v = 360 m/s,

λ�=?

λ=vν=3601200=0.3m�=��=3601200=0.3�

Example 2: All electromagnetic waves travel through a vacuum at the same speed. If a wave of frequency 7.5 GHz has a wavelength of 4 cm, then the frequency of a wave with wavelength 6 km will be (assume both are electromagnetic waves propagating in vacuum):

Options:

1. 40 kHz
2. 50 kHz
3. 5 GHz
4. 2.5 MHz

Answer: (b)