A pendulum swings in a sealed, insulated container. Its maximum height becomes smaller on successive swings because of friction and air resistance. The pendulum, Earth, air and container form a closed system. Which statement is correct?
Total energy stays constant; thermal energy rises
Total energy stays constant; thermal energy falls
Total energy falls; thermal energy stays constant
Total energy falls; thermal energy rises
115 exam-style questions on Edexcel GCSE Physics 8.1 Energy transfers and work, covering 8.1.1 Energy stores and transfer diagrams, 8.1.2 Ways of changing a system's energy, and 8.1.3 Work done by forces. Each one has a worked solution and a mark scheme showing where the marks go.