Gravity is a force. It pulls things down.

That way we don’t float up in the air.

Gravity also pulls things together.

Work is the ability to

push or pull. For instants

if I want to move this

bucket, I would have to

push or pull it so I’m

doing work.

Friction is a

complicated

thing. If you

have a

basketball and

it started to roll

it would have

to stop at

some point.

That what

Friction is. If

there was no

friction that

basketball

wouldn't stop

rolling.

Simple machines make it easy to work.

For instants I need to put a nail into the

wall. Instead of pounding the nail into

the wall with my hand I can use a

hammer. You can find all sorts of simple

machines, I can’t even name them all.