What is Friction – A Brief Outline
Friction can be defined as a force that creates resistance between the relative motions of two objects in contact. It mainly takes place due to microscopic irregularities which are present on the surface of both objects. It means that rougher the surface; the greater will be the friction between two objects and vice versa.
Additionally, two main characteristics of friction are that it always takes place in the opposite direction of relative motion between two objects and parallel to the surface of contact. Besides, the use of friction in automobiles is one of its most essential functions in our daily lives.
How Does Friction Affect Cars?
Friction in the automobile aids it to move, turn corners or slow down when necessary.
The various advantages and disadvantages of friction in automobiles have been listed below –
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When a car or any other automobile starts, its tyres push against the road. As a reaction, the friction present between the car and road pushes back which acts as a forward motion that enables a car to move forward.
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Friction in the automobile also comes in handy when a car is taking a turn at the corner of a road. As friction present between the road and tyres, wheels ‘grab’ on to the ground and stay put. It prevents a car from sliding while turning a corner, which is why a car can sometimes skid or slide on a muddy or wet road as they have less friction than regular roads.
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Apart from movement, friction in a car or automobile slows down. Disc brakes of cars have a steel disc attached to wheels which can be found between the two small brake pads. When the brakes are pressed, brake pads push the discs on the car wheels which cause friction. This slowed down the wheels and finally stopped the car.
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Apart from friction on cars, it also works the same in the case of bicycles. When the brakes on bicycles are applied, brake pads press down on bicycle wheel rims. It causes friction and slows it down.
However, friction in automobiles also generates heat which accelerates wear and tear of a car engine. Furthermore, around one-third of a car’s fuel usage goes towards overcoming friction.
Advantages and Disadvantages of Friction
In our day to day lives, friction is a necessary evil. For instance, without it, we wouldn’t be able to walk properly. Like friction in automobiles, when we walk, we push the ground with our foot, and as an opposite reaction, the ground too pushes us back.
However, friction present between the road and sole of our shoe enables us to keep our grip and prevent slipping, which is why we tend to slip and fall on wet or well-polished surfaces.
Similarly, it is because of friction we can write and draw on surfaces like paper and blackboard. When we write, bits of lead and chalk break due to friction present between them and paper. These bits then cling to the surface and appear as writing or drawing.
Types of Friction
To better understand friction and cars, one should have a detailed idea of four main types of friction –
The frictional force that occurs between two objects when they are at rest is known as static friction. In this situation, acceleration can only take place when the force applied to the one object in rest can overcome the static friction. In other words, if there is no static friction, an object or body would continue to move. Examples of static friction include when a car is parked on a hill, a ball resting on the floor etc.
Sliding friction acts on an object or body when it is motion. It is also known as kinetic friction. The resistance offered by sliding friction is weaker than static friction. It is because a body in motion stays in motion, whereas it is more difficult to overcome the static force and move an object.
The friction resisting movement of a rolling object or body is known as rolling friction. This type of friction has even lesser resistance than sliding and static friction which is one of the reasons it is easier to move a heavy object by rolling rather than by sliding.
The friction faced by an object or body when it is moving through a fluid medium is known as fluid friction. Examples include resistance faced by swimmers when swimming, Skydiver falling towards the ground using a parachute etc.