Pressure in liquids and gases
2 marks · EasyExplain why a sharp knife cuts more easily than a blunt one, using ideas about pressure.
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A sharp knife has a smaller area in contact with the object, so for the same force, it produces a higher pressure, making cutting easier.
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Marking points
B1 · 1 mark · Mentions smaller area gives greater pressure.
B2 · 1 mark · Links increased pressure to easier cutting/action.
Worked solution
A sharp knife has a small surface area, so when the same force is applied, the pressure is higher. The higher pressure allows the knife to cut more easily.