The frequency of the wave is given as 2.5 * 10^9 Hz.
The term wavelength is the distance that is covered by a wave. It is also referred to as the distance between two successive crests or two successive troughs. It can also be defined as half of the distance between two nodes.
Now nodes are the points in which there is no movement while antinodes are the points in which there is movement.
Given that;
c = λf
c = speed of light = 3 * 10^8 m/s
λ = 2(6cm) = 12 cm or 12 * 10^-2 m
f = ??
Thus;
f = c/ λ
f = 3 * 10^8 m/s/12 * 10^-2 m
f = 2.5 * 10^9 Hz
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