The table shows changes in three energy stores in a closed system. These are the only stores that change.
| Energy store | Change |
|---|---|
| Chemical | Decreases by 420 J |
| Kinetic | Increases by 150 J |
| Thermal | Increases by XXX |
Which gives X X\,X and the change in the total energy of the system?
X=570 JX=570\ \mathrm{J}X=570 J; total change 0 J0\ \mathrm{J}0 J
X=270 JX=270\ \mathrm{J}X=270 J; total change 0 J0\ \mathrm{J}0 J
X=270 JX=270\ \mathrm{J}X=270 J; total change 420 J420\ \mathrm{J}420 J
X=570 JX=570\ \mathrm{J}X=570 J; total change 420 J420\ \mathrm{J}420 J
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.