Friction

Rough surfaces make more friction than smooth ones. Friction also makes heat.

Example: A toy car rolls farther on a smooth floor than on carpet.

Lessons, worksheets, practice and tools on this: Forces and motion.

Related words

• Force: A push or a pull.
• Lever: A simple machine: a bar that turns on a point called the fulcrum.
• Magnet: An object that attracts iron and some other metals, and that has a north and a south pole.
• Gravity: The force that pulls objects toward each other, such as toward the center of Earth.

All words