Lesson K1: Forces and Gravity

Lesson K1: Forces and Gravity

Lesson K1: Forces and gravity

Main activities

K1a Mass and weight

For each group:

  • a forcemeter (Newton spring balance) reading up to 5 newtons
  • four slotted masses and hanger (either 50 g or 100 g would be suitable).

For the class:

  • electronic top-pan balance(s) recording up to 500 g
  • a stone/large rubber bung/small sand or bean bag – mass approximately half that

of the masses and hanger (i.e. 125 g or 250 g) – clearly labelled ‘A’. If possible,

have more than one of these with the identical mass

  • a similar object, of slightly different mass, clearly labelled ‘B’ – again more than

one if possible. It should be possible to hang B from the forcemeter

  • bathroom scales, calibrated in kg
  • bathroom scales, calibrated in newtons.

Lesson K2: Friction

Starter activities

Recap last lesson

  • tin of baked beans

Capture interest

  • metal object
  • oil lubricant

Main activities

K2a Shoe soles

  • For each pair/group:
  • a set of masses, 100–600 g
  • a shoe
  • a forcemeter
  • string
  • suitable surface to pull the shoe over, e.g. cork tile.

Lesson K3: Balanced forces

Starter activities

Recap last lesson

suggested materials:

  • sandpaper
  • glass
  • PTFE
  • Tape
  • Teflon-coated pan
  • floor vinyls (somecan be smooth but non-slip)

Capture interest (2)

  • toy car

Main activities

K3a Stretching

For each pair:

Core:

  • a spring
  • a clamp stand with two bosses and clamps
  • a metre rule
  • a mass holder
  • masses from 100 g to 600 g, possibly labelled with their weights in newtons.

Extension:

  • as above
  • an elastic band, about the same length as the spring.

K3b Floating and upthrust

For demonstration:

  • a forcemeter with a scale in newtons suitable to show weights of the chosenobjects
  • three or four objects that will float in water, with loops of string attached

(make sure they weigh enough to register clearly on the forcemeter in air)

  • a trough or large beaker of water, ideally transparent and calibrated, so that

level of water can be seen clearly.

For Extension demonstration:

  • two large beakers, one containing tap water and one containing the same

volume of very salty water.

Lesson K4: Unbalanced forces

Starter activities

Recap last lesson

  • toy car
  • string

Lesson K5: Slow down!

Starter activities

Recap last lesson

  • toy car

Lesson K6: Archimedes’ story – Think about

Starter activities

Concrete preparation (2)

  • cubes for density investigation

(e.g. from Philip Harris)

Main activities

K4a All unbalanced

1 Getting trolley moving:

  • a trolley
  • smooth, flat, level surface
  • a box containing screwed up paper, for the trolley to crash into.

2 Squashing a can:

  • an empty soft drinks can.

3 Trolley changing speed:

  • a trolley
  • suitable surface – smooth at first and then covered with sand or furrymaterial
  • a box containing screwed up paper, for the trolley to crash into.

4 Ball changing direction:

  • a ping pong ball
  • smooth, flat, level surface
  • a box containing screwed up paper, for the trolley to crash into.

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This list is in Microsoft Word, so it can be customised to fit each school’s requirements.