Fast and slow
Physics · Early Years · The School
Fast things and slow things
Some things move FAST. A car. A running dog. A ball thrown hard. Some things move SLOW. A snail. A cloud. Someone walking carefully. Watch two things move. You can say which one is faster. You do not need any numbers at all.
Making it faster
Push something harder and it goes faster. Roll a ball gently and it travels slowly. Give it a big push and it shoots away. A car rolling down a steep slope goes fast. The same car on a gentle slope goes slower. A bigger push means more speed. So does a steeper slope.
Stopping
Things do not keep going for ever. A rolling ball slows down and stops. Rubbing against the ground slows it. A ball rolls further on smooth wood than on thick carpet. The carpet rubs against it more. Something always slows a moving thing down.
Prop a tray on one book. Let a toy car roll down it. Mark where it reaches. Now prop the tray on three books. Let the SAME car go. It arrives faster. It travels further. A steeper slope gives it a bigger pull. Now put a towel at the bottom and run it again. It stops much sooner. Steeper means faster. Rougher means stopping sooner. Two changes, two clear results.