Question

can you give me highlighted points of chapter friction ???

Answer 1

Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. There are several types of friction: Dry friction is a force that opposes the relative lateral motion of two solid surfaces in contact.

Answer 2

Hi there!
Here's the answer:

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¶¶¶ Friction ¶¶¶¶

• Friction is a force that acts in the opposite direction of applied force.
• It opposes the relative motion between the object surfaces that are in contact.


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¶¶ Advantages of Friction:

• It becomes difficult to walk on the Ice or on a Slippery road, due to low friction.
• A horse cannot pull a cart unless friction provides the horse a secure foothold
• A nail cannot be fixed in the wall or wood without friction. It is the friction which holds the nail.


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¶¶ Disadvantages of Friction:

Despite of the advantages that friction has in our daily life, it also has some diadvantages like :

• Need of exerting More power in the machines.
• Results in production of Noise in machines
• Makes engines consume more Fuel, which is a money loss
• It Opposes the Motion.
• The Major Disadvantage is that the heat is produced in various parts of the machine. This heat in turn results in wear and tear in machines.

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¶ Methods of Reducing Friction:

Some of the methods to reduce friction are:

• Use of Lubricants
Lubricants of suitable viscosity must be applied to the machine parts

• Use of Ball Bearings
It replaces sliding friction by rolling friction in machines wherever its possible.

• Modifying Design
Fast moving object' s design if changed accordingly, friction can be reduced.
Eg. : Front of vehicles and aeroplanes are made oblong to reduce the friction

• Use of grease
Greasing properly between the sliding parts of machine can reduce the friction


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Hope it helps