What is the effect of friction on the motion of an object?

Friction is a force that arises when two surfaces come into contact, and it acts parallel to the surfaces. Its primary effect is to oppose motion. When an object is in motion, friction works against the direction of that motion, slowing it down or stopping it altogether. This resistance is crucial in various everyday scenarios, such as when walking, where friction between your shoes and the ground allows you to push off effectively without slipping.

Additionally, friction can play a role in preventing or initiating movement; for example, a stationary object will remain at rest until the force applied to move it exceeds the static friction that resists that initial motion. In essence, friction is key to understanding how motion is controlled and influenced in mechanical systems, as it often determines the amount of force needed to start or maintain movement.