WHEELS AND BELTS (small group presentation)
To observe how a belt turns a wheel.
A rectangular block of wood with two nails driven into the middle approximately seven to eight centimetres apart.
Two spools the same size, one resting on each nail.
A wide rubber band is slipped over both spools.
One large and one small spool.
Invite a child to join you and carry the materials to a table.
Give one spool a complete turn.
Observe the other spool.
Invite the child to try.
Note that the other spool makes a complete turn, moves at the same speed and turns in the same direction.
Now cross the rubber band so that it makes a figure eight.
Have the child give one spool a complete turn.
This time the driven spool will turn in the opposite direction.
Repeat both activities, using a smaller and a larger spool this time.
Observe the action of the driven spool.
When finished, replace the material.
As in presentation.