How does friction affect motion?

How does friction affect motion?

• A. It speeds up moving objects
• B. It has no effect
• C. It opposes motion and can slow or stop moving objects, converting some kinetic energy to heat
• D. It makes objects oscillate

Answer: (C)

Friction is the contact force that resists slipping between surfaces. When something moves, friction acts in the opposite direction to its motion, slowing it down and potentially stopping it. The kinetic energy of the moving object is transformed into heat at the contact points, warming the surfaces a little. For example, sliding a book across a desk slows it to a stop due to friction, and brakes turn kinetic energy into heat to slow a car. Friction doesn’t speed up motion in straight-line movement, and it’s not what causes objects to oscillate.

Friction is the contact force that resists slipping between surfaces. When something moves, friction acts in the opposite direction to its motion, slowing it down and potentially stopping it. The kinetic energy of the moving object is transformed into heat at the contact points, warming the surfaces a little. For example, sliding a book across a desk slows it to a stop due to friction, and brakes turn kinetic energy into heat to slow a car. Friction doesn’t speed up motion in straight-line movement, and it’s not what causes objects to oscillate.