A hot metal block and cooler water are placed in an insulated container. The block transfers 300 J to the water. No energy crosses the outside boundary. Which statement describes the block and water together?
Total change +300 J+300\ \mathrm{J}+300 J; transfer by heating
Total change 0 J0\ \mathrm{J}0 J; transfer by heating
Total change +300 J+300\ \mathrm{J}+300 J; transfer by forces
Total change 0 J0\ \mathrm{J}0 J; transfer by forces
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.