A spacecraft transmitter sends a microwave signal through a vacuum to a detector on a distant probe. The signal takes 4.0 min to reach the detector.
A radio signal is sent at the same time along the same route. Explain whether it would reach the probe before, after or at the same time as the microwave signal.
The speed of microwaves in a vacuum is 3.0 × 108 m/s.
Calculate the distance travelled by the microwave signal before it is detected.
84 exam-style questions on Edexcel GCSE Physics 5.2 The electromagnetic spectrum, covering 5.2.1 Electromagnetic waves and refraction in glass (core practical), 5.2.2 Groups of the electromagnetic spectrum, 5.2.3 Wavelength-dependent behaviour of EM waves, and 5.2.4 Velocities of EM waves in different substances. Each one has a worked solution and a mark scheme showing where the marks go.