What does friction do to an object's motion?

Friction plays a crucial role in the motion of objects by opposing the relative motion between surfaces in contact. When two surfaces rub against each other, friction acts against their motion, which can result in slowing down the movement of an object or bringing it to a stop. For instance, when you slide a book across a table, friction between the book and the table surface is what eventually brings the book to a halt. It converts the kinetic energy of the moving object into thermal energy, causing the object to lose speed until it stops or slows down significantly.

Understanding this fundamental concept is vital, as it applies to everyday experiences, such as walking, driving, or even playing sports, where friction is necessary for controlling motion. In situations where there is little to no friction, objects would continue to move indefinitely until acted upon by another force, demonstrating the importance of friction in motion dynamics.