This PSEB 8th Class Science Notes Chapter 12 Friction will help you in revision during exams.
PSEB 8th Class Science Notes Chapter 12 Friction
→ Force opposing the motion of the body is called the force of friction.
→ Force of friction acts between any two surfaces in contact with each other.
→ Friction depends upon the nature and smoothness of the surface.
→ Friction is due to irregularities on the two surfaces in contact.
→ Friction increases with pressure.
→ Sliding friction is less than static friction.
→ Friction is both a friend and a foe.
→ Friction is a necessary evil.
→ Friction can be increased or decreased as per requirement.
→ Wheels reduce friction.
→ Lubricants are substances that can reduce friction.
→ The frictional force exerted by fluids is also known as drag.
→ Frictional force in fluids depends upon the speed, nature of the object, and shape of the object.
→ Streamlined objects offer less friction in fluids.
→ Friction: A force which opposes the relative motion between the two surfaces in contact is called friction.
→ Static Friction: A force that counterbalances the applied force on a body is static friction.
→ Sliding Friction: A force that exists between any two sliding surfaces is sliding friction.
→ Rolling Friction: A friction that comes into play between two rolling materials is called rolling friction.
→ Fluid Friction: A force exerted by the fluid on the object immersed in it, is called fluid friction.
→ Streamline: A particular shape that offers little resistance in air or water.
→ Fluids: The name given to air and liquids together.