A space probe near Mars sends radio signals back to the Earth.
At the time the signals are sent, the distance from the probe to the Earth is 2.25 × 1011 m.
The speed of radio waves in space is 3.0 × 108 m/s.
Calculate the time taken for the signals to reach the Earth.
Give your answer in minutes.
A distant star explodes. It emits a burst of gamma rays and a flash of visible light at the same moment.
Explain why the gamma rays and the visible light arrive at the Earth at the same time.
The radio signals from the probe have a wavelength of 3.6 cm.
Calculate the frequency of the radio signals.
48 exam-style questions on OCR GCSE Physics 5.2 The electromagnetic spectrum, covering 5.2.1 Electromagnetic waves in space, 5.2.2 Energy transfer by electromagnetic waves, 5.2.3 Frequency and wavelength across the spectrum, 5.2.4 Groups of the electromagnetic spectrum, 5.2.5 Visible light and the limits of human sight, 5.2.6 Light as an electromagnetic wave, 5.2.7 Uses of electromagnetic waves, 5.2.8 Hazards of ultraviolet, X-rays and gamma rays, 5.2.9 Ultrasound and imaging inside the body, and 5.2.10 Radio waves and oscillating circuits. Each one has a worked solution and a mark scheme showing where the marks go.