The questions are on the forms of energy test. Take it under real conditions before reading the mark scheme.
Quick answer: Energy is the ability to make things change, and it is measured in joules (J). This mark scheme gives the model answers and the marks for the 8 questions of the grade 6 science test on forms of energy, from naming forms to campfire, with the equivalent answers to accept.
Model answers and mark allocations are given for every question. Award marks for correct reasoning even when the wording differs, and check that energy chains name the right form at each stage.
Level: Grade 6 science (Year 7 · Class 6) · Curriculum: MS-PS3
Question 1 Naming forms (2 marks)
The gas cylinder stores chemical energy. The hot milk has thermal energy.Marking: 1 mark for each correct form.
Question 2 Solar street lamp (3 marks)
Day: light → electrical → chemical (stored in the battery). Night: chemical → electrical → light (and thermal).Marking: 1 mark for the day chain, 1 mark for the night chain, 1 mark for the stored form being chemical.
Question 3 Conservation (2 marks)
Energy is never created or destroyed, only transformed. The kinetic energy of the ball was transformed into thermal energy of the grass and the ball (and a little sound), so it spread out but did not disappear.Marking: 1 mark for the law, 1 mark for the thermal energy explanation.
Question 4 Diesel generator (4 marks)
- 400 − 100 = 300 J.
- 100 ÷ 400 × 100 = 25 %.
- It spreads into the surroundings and warms the air and the engine.
- Use a more efficient engine, or reduce friction with good lubrication.
Marking: 1 mark for each part.
Question 5 LED torch (2 marks)
9 ÷ 12 × 100 = 75 %.Marking: 1 mark for the method, 1 mark for the answer with unit.
Question 6 Energy sources (3 marks)
Renewable: wind and sunlight. Non-renewable: coal and oil. Renewable sources are replaced naturally as fast as we use them, whereas non-renewable sources take millions of years to form and will run out.Marking: 1 mark for two correct renewable examples, 1 mark for two correct non-renewable examples, 1 mark for the explanation.
Question 7 Cooking choices (2 marks)
Solar cooker: free and renewable, no smoke. Charcoal: works at night and in cloudy weather.Marking: 1 mark for each advantage.
Question 8 Campfire (2 marks)
Thermal energy and light energy, transformed from the chemical energy stored in the wood.Marking: 1 mark for each form.
