What are the Disadvantages of Friction?

Friction causes the physical degradation of materials over time.

• Examples: The soles of our shoes wear out and become flat. The rubber tires of cars become bald and dangerous after running on the road for thousands of kilometers. Machine parts grind against each other and eventually break.

Friction acts as a resisting force. When you try to move a heavy box across the floor, or when a car engine tries to turn the wheels, a significant portion of the applied energy is wasted just fighting against the friction.

When two rough surfaces rub against each other rapidly, friction generates massive amounts of heat.

• The Problem: In car engines and industrial machines, this unwanted heat can cause the metal parts to melt, expand, or catch fire. We have to spend even more money to install cooling systems (like radiators) just to counter this frictional heat.

Friction from the air (air drag) and water (fluid friction) slows down moving vehicles. Cars, airplanes, and ships have to be specially designed with streamlined (aerodynamic) shapes just to cut through this friction, otherwise, they would consume too much fuel.