What is the period of oscillation in a circuit emitting radio waves with a wavelength of 0.5 km.

Given:
l = 0.5 km (kilometers) – the length of the radio wave;
c = 3 * 10 ^ 6 km / s = 3 * 10 ^ 8 m / s (meters per second) – the speed of propagation of radio waves in a vacuum.
It is required to determine T (seconds) – the period of the radio wave oscillations.
We will convert the units of measurement of length to the SI system:
l = 0.5 km = 0.5 * 1000 = 500 meters.
Then, to determine the period of oscillation, you must use the following formula:
c = l / T, from here we find that:
T = l / c = 500 / (3 * 10 ^ 8) = 166.7 * 10 ^ -8 = 1.7 * 10 ^ -6 seconds (the result was rounded up to one tenth).
Answer: the period of oscillation of a radio wave is 1.7 * 10 ^ -6 seconds (1.7 milliseconds).