A local radio station tests a new transmitter. A household radio receiver several kilometres away picks up the broadcast. The radio waves travel through air at the same speed whatever their frequency.
The transmitter first broadcasts at 90 MHz. It can be switched to 45 MHz, 90 MHz or 180 MHz.
Engineers change the setting, and the wavelength of the broadcast radio waves becomes twice its earlier value.
Which pair gives the new transmitter frequency and the frequency of the electrical oscillations induced in the household receiver?
transmitter frequency: 45 MHz; receiver frequency: 90 MHz
transmitter frequency: 180 MHz; receiver frequency: 90 MHz
transmitter frequency: 180 MHz; receiver frequency: 180 MHz
transmitter frequency: 45 MHz; receiver frequency: 45 MHz
104 exam-style questions on Edexcel GCSE Physics 5.4 Uses and dangers of EM radiation, covering 5.4.1 Dangers of electromagnetic radiation, 5.4.2 Uses of electromagnetic radiation, 5.4.3 Radio waves and oscillations in circuits, and 5.4.4 Changes in atoms and nuclei generating radiation. Each one has a worked solution and a mark scheme showing where the marks go.