Friction is a force that opposes motion between two surfaces that are touching. It tries to slow down or stop objects that are moving or trying to move.
What Causes Friction?
Even smooth surfaces have tiny bumps. When two surfaces rub against each other, these bumps catch on each other, causing friction.
Types of Friction:
Static Friction – Stops an object from starting to move.
Sliding Friction – Acts when an object is already moving over a surface.
Rolling Friction – Acts on objects that roll, like wheels.
Air or Fluid Resistance – A type of friction when objects move through air or liquid.
Is Friction Good or Bad?
Useful: Helps us walk, stops cars with brakes, and keeps objects from sliding.
Not useful: Causes parts to wear out, makes machines less efficient by wasting energy as heat.
How Can We Reduce Friction?
Use lubricants like oil or grease
Use smooth or polished surfaces
Use ball bearings or wheels