Friction
Definition.
Friction is a force that opposes the motion of two surfaces that are in contact with each other.
Types of friction.
Static friction – keeps an object from moving.
Sliding friction – slows things sliding.
Rolling friction – slows rolling objects.
Air resistance – friction with air.
Key Points about Friction.
Friction is a force.
It acts between two surfaces that are touching.
Friction opposes motion.
It slows down moving objects.
Rough surfaces create more friction than smooth ones.
Friction can produce heat.
It helps us walk, write, and stop vehicles.
Too much friction causes wear and tear.
Friction can be useful or harmful.
Friction is measured in newtons.
How friction works.
Surfaces are not perfectly smooth.
They have tiny bumps and ridges.
When two surfaces touch and try to move, these bumps catch on each other.
This resists the movement and slows it down.
That resisting force is called friction.
Why friction is important.
Friction is important because it helps us control movement in everyday life.
Key reasons.
It helps us walk without slipping.
It allows us to hold and grip objects.
It helps vehicles stop using brakes.
It lets us write with a pencil or pen.
It helps clothes stay on our body.
It makes things stay in one place.
Fun fact.
Meteorites burn up when entering Earth’s atmosphere because of extreme friction with air.