## What is friction?

In simple language, Friction is known as resistance to motion.

When the two bodies are in contact with each other and if there is a relative motion between them then the motion of each body is resisted in opposite direction, this resistive force is known as frictional force.

The amount of friction between two surfaces is characterized by the coefficient of friction (μ).
The value of the coefficient of friction varies from 0 to 1.

0 < μ (Coeficient of friction) < 1

There is a number of advantages and applications of friction such as walking on the ground, power transmission by belt, stopping of the vehicle because of friction and it also has disadvantages which even cause wear and tear of machine components, decrease in the life of machines, etc.

1) Many types of motion are possible: The friction causes resistance to the motion of body which allows the tires of the vehicle to move onto the road without skidding.

2) Walking on the ground is possible: To move in the forward direction when we try to push ground in a backward direction the resistive force between our shoe and ground works in the opposite direction of applied force and hold our shoe firmly on the ground. Hence we can walk onto the ground without skidding.

3) Stop the vehicle in motion using brakes: When we apply the car brake, the brake shoes are rubbed onto the brake drum which causes the brake drum to stop the motion.

4) Heat generation: When the two surfaces are rubbed on each other, the heat is generated between the surfaces. In the winter season, we can rub our hands on each other which gives a warm effect to us.

5) The objects can be hold: Because of an adequate amount of friction we can hold any object in our hand.

6) Writing on paper: Because of the frictional resistance of the ball, the pen can’t skid on the paper hence ink can be easily placed onto the paper.

7) Spark or fire can be generated: In ancient times friction is used to generate spark or fire.

8) Power can be transmitted using belt and rope drive: Because of frictional resistance between pulley and belt or pulley and rope, we can transmit power from one shaft to another shaft.

9) To hold objects on an inclined plane: The resistive frictional force can oppose the downward movement of an object on an inclined plane and we can hold an object on an inclined plane.

10) Asteroids are burned in the atmosphere: When the asteroids come into the earth’s atmosphere, the motion of the asteroid is opposed by the earth’s atmosphere. Because of the friction between asteroid and atmospheric air the heat is generated in a large amount which burns the asteroid before it reaches the ground.

1) Extra effort required: As the frictional force acts in the opposite direction of motion hence it is required to overcome that frictional force to move objects from one place to another.

2) Motion is slow down: Some part of the energy is utilized to oppose the frictional force hence the motion of any object is slowed down.

3) Waste of energy in heat generation: To overcome friction losses the extra energy is wasted in the generation of heat which cannot be recovered.

4) Loss of power: To overcome the frictional resistance between the components of any machine the extra amount of power is wasted.

5) Wear and tear: As the two surfaces in contact are rubbed with each other, the surfaces of contacting bodies undergo wear and tear which leads to the lower life of components.

6) Efficiency of the machine decreases: As the motion has to provide more energy to overcome friction losses hence the overall efficiency of the machine decreases.

7) Noise is generated: The friction between two surfaces can cause the generation of irritating noise.

8) Wildfire: In wild areas, the friction between two trees causes the generation of wildfire which burns the entire forest.

FAQ:

Q.1 What are advantages of friction?

The advantages of friction are Many types of motion are possible, Stop the vehicle in motion using brakes, Write on paper, etc.

Q.2 What are the main disadvantages of friction?

The main disadvantages of friction are Extra effort required, Loss of power, Noise is generated, etc.