Radio signals from a space probe near Saturn take 75 minutes to reach Earth.
Radio signals from a lander on Mars take 15 minutes to reach Earth.
Calculate how many times further the Saturn probe is from Earth than the Mars lander.
State the property of electromagnetic waves that you used to make this calculation.
26 exam-style questions on Edexcel GCSE Physics 5.2 The electromagnetic spectrum. Each one has a worked solution and a mark scheme showing where the marks go.