In which of these situations is the most work done against gravity?
A 4 kg4\text{ kg}4 kg cat climbing 8 m8\text{ m}8 m vertically upwards
A 90 kg90\text{ kg}90 kg firefighter climbing 12 m12\text{ m}12 m vertically upwards
A 12 kg12\text{ kg}12 kg dog climbing 25 m25\text{ m}25 m vertically upwards
A 70 kg70\text{ kg}70 kg hiker climbing 15 m15\text{ m}15 m vertically upwards
28 exam-style questions on OCR GCSE Physics Work done. Each one has a worked solution and a mark scheme showing where the marks go.