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In The Name Of ALLAH The Most Merciful and The Most Beneficent

FRICTIONMade by :-

UsmAN RajpOot

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Contents

What is friction ?

Advantages of Friction

Disadvantages of friction

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What is Friction ?

Friction (frictional force) is a force that acts in a opposite direction to movement.

The force which always opposes the motion of one object over another, object in contact with it , is called friction.

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Advantages of

Friction

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1.Friction enables us to walk without

slipping It is because of the friction between the sole of the shoe and ground prevents us from slipping.

While walking , we push the ground backwards and the force of friction acts in the opposite direction (i.e. in the forward direction) and prevents us from slipping. By making the balance.

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Walking

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Friction helps us to walk

Walking on slippery ground is difficult because friction on slippery ground is less due to which we may slip.

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2.Friction enables a car to move on road without skidding

It is because of the friction between the tyres of car and the road which enables car to move forward without skidding.

If there were no friction , car would stay where it was.

CAR MOVE DUE TO THE FRICTION

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2.Friction enables a car to move on road without skidding

It becomes sometimes difficult to drive and control car on wet road.

This is because of water present on road reduces friction.

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3.Friction Enables Us to Write and Draw on Paper

It is because of the friction between the tip of the pencil ( or pen) and paper.

Carbon particles from the pencil lead rubs off from it, due to the friction, which appears as black marks on the paper.

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4.Friction Enables Us to Pick Up and Hold Things

in Our Hands We can hold a glass tumbler in our hands

because of friction between the tumbler and our hands.

Similarly, we can pick up the books laying on the desk by our hands.

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5.Friction Enables us to Light a Matchstick

Friction also produces heat. We rub matchstick against the rough side

of a matchbox, then friction between both of them produces heat and this heat burns chemicals present at the head of matchstick and it lights up.

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Disadvantages of Friction

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1.Friction Wears Away the soles of Our Shoes

When we walk on the road, tiny surfaces of the shoe keep on breaking off slowly due to which the soles of our shoes wear out slowly

Due to which shoes get damaged and becomes unfit to wear.

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2.Tyres of Vehicles Wear out Gradually Due to

Friction Like the shoe tiny particles of tyres also

breakdown due to friction when they run on road.

The same thing also happens with the bicycles

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Effect to Tyres Due to Friction

Before After

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3.Friction wears Out the Brake Pads of Vehicles

Gradually Brake pad is made of rubber When the brakes of the vehicles are

applied a lot of friction is produced Friction wears out the brake pads

gradually

Before - After

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4.Friction wears Out Steps Of Staircases in

Building and Foot Over-Bridges

The friction between the soles of the shoes and wear away hard stone steps slowly.

Such type of staircase are usually seen at :

Railway station Old Buildings

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5.Friction Slows Down Motion

Friction reduces the motion of moving parts of a machine . In fact all the moving things such as (cars , buses, airplanes, boats, ships ,etc.) are slowed down by friction.

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Ways to increase friction

New materials with more bumps and hollows are produce for making car brakes lining.

New styles for the soles of athletes’ shoes. Its aim is for runners to run with greater speed.

Ways of reducing friction

Smoothing out Surface ex. Applying floor wax and scrubbing

the floor.

Placing a slippery substances between two solid surfaces

ex. Grease, oil and other lubricating liquids

Using rotating objects ex. Roller bearings, ball bearings and wheels

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