NCERT Solutions for Class 8 Science Chapter 12:Friction

In this chapter, we will study the topic of friction in great detail. The chapter begins by telling us about friction as a force. Then we learn about the various factors that affect friction. The chapter also tells us about ways to increase and reduce friction. We also study fluid friction and various experiments to observe it.

• Friction opposes the relative motion between two surfaces in contact.
• The intensity of friction also depends upon the smoothness of the surfaces.
• The chapter portrays various experiments to test friction on different surfaces, both rough and smooth.
• The chapter also tells us why friction is necessary in our lives.
• We read about an everyday life situation that depends on friction.
• For example, we would not be able to write with pens and pencils on paper if friction did not exist.
• We also learn about ways to increase and decrease friction.
• Lubricants are used to reduce friction.
• On the other hand, the soles of our shoes and the tyres of our cars are grooved and threaded respectively to increase friction.
• In many machines, ball bearings are used to reduce friction.
• The chapter also teaches about static friction, sliding friction, and rolling friction.
• Sliding friction is smaller than static friction.
• There is also a type of friction called fluid friction.
• Gases and liquids are also referred to as fluids.
• The frictional force exerted by these fluids is also called drag.