A student uses a Geiger-Müller tube to measure the background radiation count in a classroom. They record the counts over several 10-second intervals and calculate an average count rate.
Give one reason why any future measurement of the background radiation count over a 10-second interval is only an estimate.
90 exam-style questions on Edexcel GCSE Physics 6.3 Nuclear equations and decay, covering 6.3.1 Beta-minus and beta-plus decay, 6.3.2 Effects of decay on the nucleus, and 6.3.3 Balancing nuclear equations. Each one has a worked solution and a mark scheme showing where the marks go.