Science
How does friction work?
Friction works at the microscopic level: even surfaces that look smooth are covered in tiny bumps that catch on each other. When you slide one surface over another, those bumps interlock and resist — and the harder the surfaces press together, the stronger the grip.
See it in motion.
Watch a 2-minute animated lesson that shows exactly how friction works.
Step by step
- 1Tiny surface bumps catch and interlock.
- 2Harder pressing means more friction.
- 3Static friction holds; kinetic friction slows sliding.
- 4The resistance turns movement into heat.
Frequently asked questions
- How does friction work?
- Microscopic bumps on two surfaces catch on each other; sliding must overcome that grip, which resists motion and creates heat.
- Why is it harder to start sliding than to keep sliding?
- Static friction (at rest) is stronger than kinetic friction (already moving), so the first push needs more force.
- Why does rubbing make heat?
- Overcoming friction converts movement energy into heat at the contact surfaces.