October 25, 2010
They talked about how simple machines can make life easier.
Without wheels there is a lot of friction.
They tried out moving things on different surfaces and texture.
Then they check out how far different cars could go on different slopes.
Build the lawn mover.
One kind can turn easily and the other has too much friction.
A single axle for both front wheels makes too much friction.
Whhen each wheel is on its own axle the wheel can turn independently.
