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| | ==Outcomes== | | ==Outcomes== |
| − | * Pupils can explain that drag increases with velocity | + | * Pupils can ... |
| − | * Pupils can appreciate why objects reach terminal velocity | + | * Pupils can ... |
| − | * Pupils can identify the factors which affect terminal velocity
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| | ==[[Specifications|Specification]] References== | | ==[[Specifications|Specification]] References== |
| − | 1.16 describe the forces acting on falling objects and explain why falling objects reach a terminal velocity
| + | ==Starter== |
| − | ==Starter== | + | |
| − | Guinea and Feather Demo - ask what will happen when we drop both in air. Then demonstrate the difference when both are dropped in a vacuum (using th evacuated tubes). Try to get the pupils to deduce what forces are acting. You can also show the Neil Armstrong [http://www.youtube.com/watch?v=PE81zGhnb0w video]
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| − | OR
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| − | a)Drop a sheet of A4; falls slowly due to drag
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| − | b)Crumple it up; mass remains unchanged but falls quicker due to less drag
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| − | c)Place the A4 on a big book and drop; big book removes the effect of air resistance
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| − | d)Drop a ream of A4; all sheets fall at the same rate
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| | ==Main Body of Lesson== | | ==Main Body of Lesson== |
| − | Terminal velocity in Glycerol and Air:
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| − | 1) Glycerol - demonstrate how tiny ball bearings achieve TV in glycerol. Can be made more visible with some white paper behind with unifromlly spaced lines on
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| − | 2) Air - drop a parachute person with some PASCO tape on, should reach TV if dropped from high enough
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| − | Make notes on how velocity affects drag, terminal velocity and the classic skydiver example.
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| | ==Plenary== | | ==Plenary== |
| | ==Homework== | | ==Homework== |
