Forces Make Things Move

Forces Make Things Move

If you push a toy car, you can make it move across the floor. Your push moves the car. Your push is a force. Forces get things moving. Forces also make things stop. When the toy car rolls across the floor and stops, a force stopped it. Forces also make things speed up or slow down.

Any push or pull is a force. Forces can move things farther away or bring them closer. Some forces are very strong. Some are so weak, you can't feel them at all. Nothing starts moving until it is pushed or pulled. If you don't push your toy car, it just sits there--unless something else pushes it, like the wind or your cat or your big brother. The wind, your cat, and your big brother can all produce force. The force moves your car. Any time your car is moving, a force made it start. The heavier an object is, the more force it takes to start it moving. If you want to run across the yard, your feet have to push on the ground to get you moving.

If you and your big brother decide to have a race, his feet will have to push harder on the ground than yours. Why? Because he weighs more. It takes more force to make him move. Once you are running, only another force can stop you. Your feet push on the ground to make you stop. If you want to stop quickly, it takes more force than if you want to stop slowly. You'll have to push harder.

It takes a lot of force to start heavy things moving. That's why your living room couch doesn't fly across the room when you bump into it. It's why a breeze can't blow your family's car off the driveway. Other things, like leaves and papers and hats, don't weigh very much. Even tiny forces can make them fly around. A little wind makes enough force to make them move.

But if your big brother is lying on the living room couch, you're going to have to push pretty hard to force him off.