question_answer

An electromagnetic wave has a frequency of 500 MHz and a wavelength 60 cm. Name the medium through which it is travelling.

Answer:

Given, \[n=500\text{ }MHz=500\times {{10}^{6}}Hz\]                                 \[\lambda =60cm=\frac{60}{100}m\]                                 \[v=?\] We know, \[V=n\lambda =500\times {{10}^{6}}\times \frac{60}{100}\]                                 \[=3\times {{10}^{8}}m/s\] \[\therefore \]the medium must be air / vacuum.