Friction is a type of force that keeps objects in place or slows them down. This lesson explores friction in greater detail and provides examples of friction in action.
What Is Friction?
Friction is a special kind of force. But what’s a force? Forces are pushes or pulls that can change the motion, or movement, of objects. If you pushed or pulled a box of books across the floor, you would be using force to move the box.
But there are other forces affecting that box of books besides your pushes or pulls.Let’s say you’re trying to push that box from one end of your bedroom to the other end. As you push it, the box will move, but there’s also a force acting in the opposite direction of your push. This force, called friction, will stop the box from moving when you stop pushing it.
More or less friction can be produced depending on the surface of the objects. If your bedroom has carpet instead of wood, pushing that box of books will be a very different experience! Moving the box across carpet will result in a lot more friction than moving the box across a slick wood floor. It will be much harder to move the box across carpet because there’s a lot of friction between the carpet surface and the box surface.
Examples of Friction
We may not always be thinking about friction, but it’s something that affects our everyday lives. Friction can actually be very useful.
Think about a box of matches. When people light matches, they rub the matches across the rough surface on the side of the box. This movement creates enough friction to ignite matches.Friction forces can create a lot of heat.
Think about what you do when your hands get cold on a winter day. You rub them together! That’s because the rubbing creates friction, which creates heat that helps your hands warm up. Try rubbing your hands together very quickly. You will start to feel a lot of warmth in the palms of your hands.Another way friction is useful is that it can help keep you safe when you’re in a car or on the bus. When a bus driver hits the brakes to avoid a wreck, the friction between the road and the wheels of the bus helps the bus stop quickly.When you’re working on your writing homework and you realize you spelled something wrong, what do you use to correct the mistake? You use an eraser to erase the mistake.
Another example of friction in action! Friction between the eraser and the paper helps to rub out those pesky spelling mistakes.
To review, friction is a special kind of force that slows down or stops motion. It works against the direction of a moving object, and it can generate heat. Friction is important for many daily activities, like lighting matches, driving cars, and using pencils.