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KS3/4 Science - Physics for Non-Physicists: Forces



Forces is one of those subjects that science teachers can find difficult to teach, particularly if physics is not their specialism. In this programme, Steve Hearn from the Institute of Physics visits a group of physics non-specialists from the London Borough of Barnet to offer up ideas on how to approach this subject.

Steve starts his introduction to forces with a bazooka: a homemade, partially evacuated tube which fires missiles at a target. He discusses how the bazooka works and what forces are acting on the missile, and the teachers draw their own force diagrams.

Steve then goes on to introduce a bubble investigation where air bubbles are released in glycerol and rise up a small container.

David Crossley, a teacher on the Teach First scheme, tries out the bubble investigation with a Year 7 group, asking them:

  • Which bubble will reach the top first, the big one or the small one?
  • What forces are acting on the bubbles?

The teachers and the pupils make their predictions with some surprising results.

Published : Oct 2005

15 mins


Secondary Teacher


Secondary Science


Forces and motion


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