An electromagnetic wave has a frequency of 500 MHz and a wavelength of 60 cm.

(a) Calculate the speed of the wave.

(b) Name the medium through which it is travelling.

(a) As we know,

Velocity of wave (c) = frequency (f) x wavelength (λ)

Given,

f = 500 MHz

Hence, f = 500 x 10⁶ Hz or

f = 5 x 10⁸ Hz

λ = 60 cm

As 100 cm = 1m

Therefore,

60 cm = $\dfrac{60}{100}$ m

Hence, λ = 0.6 m

Substituting the values in the formula above we get,

$c = (5 \times 10^8) \times 0.6 \\[0.5em] \Rightarrow c = 3 \times 10^8$

Hence,

Speed of the electromagnetic wave = 3 x 10⁸ ms^-1

(b) The electromagnetic wave is travelling through air.