A maintenance platform is raised vertically at a steady speed inside a tower. The platform rubs against guide rails as it moves.
The table shows measured energy changes as the platform moves through two sections of the tower.
| Section | Vertical distance moved (m) | Increase in gravitational potential energy store (J) | Energy transferred to thermal stores (J) |
|---|---|---|---|
| A | 4.0 | 7200 | 800 |
| B | 6.0 | 10 800 | 1800 |
Calculate the force exerted by the cable while the platform moves through section A.
An engineer claims that the cable exerts the same force in section B. Predict the energy transferred to thermal stores in section B if the claim is correct. Evaluate the claim using the measured value.
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.