work based ba pte year 2 science in the primary years

Work Based BA PTE Year 2

Science in the Primary Years

Unit 5 Session 1Forces 1

Learning objective:

•To deepen personal understanding about the nature of forces

National CurriculumSee unit notes

Brainstorm:

What do you understand by the word ‘force’?

A force is:A force is:

• a push

or• a pull

How can a large cardboard box and a small student assist in the teaching of forces?

What forces are acting on the student?

gravity

Why does she not move down through the floor if gravity is pulling her down?

Gravity

Contact force

Gravity

Contact force

Push!

Gravity

Contact force

Push!

Friction

Some key ideas

A force is measured in:

ons s

Newtons!

Forces have effects in different directions

Forces can be added

gravity

Contact force

Push

Forces can balance

Push

A force is a vectorA force is a vector

It has:• size

and • direction

Spend 5 minutes on each of the 2 activities on the handout:

1. Feeling and measuring forces (in pairs)2. Heave Ho! Adding forces together (in a group of 6ish)

Contact forces and non-contact forces

• Read Summary of Scientific Ideas on Forces

Unit notes pp 3-11

There are only a few different types of forces:• gravitational• electric• magnetic (related to electric)• strong nuclear• weak nuclear

Every movement that starts or stops requires a force.

Three common forces are:• gravity (weight)

• contact force (reaction force)• friction

Circus of 4 activities – see handouts

• Contact Force 1• Contact Force 2• Friction 1• The cause of friction

Weight (gravity)

Contact force

Forces can balance

Summary of key points

What does this show?

The contact force with a surface is caused byspringy atoms

push

friction

Friction

Resistance due to distortion of bristles

A rather sad comb!

What causes friction?

Analogous to two surfaces in contact

Why don’t the Australians drop off?

What causes gravity?

‘The core is like a big magnet.’

‘Is it because the world is spinning?’

Mass attracts mass

Sorry…no excuse

‘Pencils produce gravity but not enough to attract anything.’

‘If you push the two books out in a space craft, in a few days they would gradually pull together…where there’s no friction.’

‘It’s a force that pulls things to the centre of the earth.’ ‘It makes things fall’

‘It causes the tide to come in.’

‘I think it’s a force that grows in outer space and it picks up rubble and pulls it together.’

Concept cartoon 11.6

Discuss skateboard example

Required Reading:• Johnsey et al. (2002) Chapter 9 • Sharp et al. (2002) pp.91-92

Also:

Explore/read the Handout – plenty of useful information!