MEASURES TO SCALE BACK FRICTION
1. Friction is reduced when the realm of contact between the 2 rubbing surfaces is reduced. this is often through with the assistance of rollers. For this wheels are provided to the objects. Wheeled objects move with ease. Wheels not only reduce the realm of contact between two surfaces but also move smoothly. you would possibly have seen labour moving heavy machinery crates or logs of wood on cylindrical logs of wood.
2. you would possibly have observed the difference within the motion of wheels on a bullock cart and therefore the motion of wheels on a car. The difference is thanks to three reasons: that the wheels in an exceeding car are supplied with ball bearings along the axle,
the tyres are made of rubber, and (iii) the tube and tyres are inflated full of air). In bullock carts, generally ball bearings and rubber tyres don’t seem to be used. The use of ball bearings and inflated rubber tyres reduce friction.
Rolling Friction: you have got learnt about static friction and also the sliding friction. after you make use of rollers to cut back friction and roll on the objects on rollers, the friction is reduced. The force of friction between the rollers on a body and therefore the surface is termed the rolling friction. Rolling friction is far from sliding friction.
Sliding friction is reduced with the employment of rollers. it’s further reduced with the employment of ball bearings and rubberised inflated tyres.
3. Making the surfaces smooth reduces friction. Cemented roads are smoother than charcoal. Plastic is a more durable and friction-reducing material.
You already know that railroads (railway lines) and wheels on the train are made up of iron (steel). they’re smooth and hard. This reduces friction to great extent.
4. Lubrication helps in reducing friction. Machines are oiled from time to time. The bearings and other parts rubbing on each other are greased to cut back friction. In heavy machines graphite (a type of carbon) is employed as a lubricant.
5. Shaping the fast-paced vehicles. The vehicles are streamlined, that is, a selected fish or bird-like shape is given to the vehicles. they’re pointed or narrow before and curved on sides. The boats, ships, and aeroplanes are specially designed in this fashion to cut back friction from water and air.
It would now be easier to know why birds keep their beaks ahead and legs folded while flying
6. Using fine powder reduces friction. Graphite powder is employed in machines as a lubricant. Fine talcum is employed on a carom board to enable ‘coins’ to slip smoothly. Fine granules from powder function as rolling balls under the coins on the carom board.
The brakes on Vehicles
To reduce speed or to prevent a moving bicycle or other vehicle brakes are used. brakes include “brake pads” which are placed parallel to the inner rim of the wheels. While in motion the constraint doesn’t touch the wheels. As and when the vehicle is to be stalled immediately or stopped, the brake lever is pressed. The lever brings the constraint in close contact with the rim of the wheels. This leads to friction between the brakes and therefore the moving wheel.
CAN WE DO WITHOUT FRICTION?
Friction is Important
1. Friction helps us in walking conveniently. it’s quite common finding people skid while they walk on the wet and oily floor. you will slip and fall. The same may happen once you walk on wet cemented or tiled floors with a smooth rubberised sole on your shoes. On hills, the snow attack roads make it extremely slippery. most of the people skid while walking on snow. The same is true about vehicles. Vehicles skid on snow. Tyres on vehicles are covered with iron chains to extend friction and help them march on snow. you may have seen people doing “Ice skating” wearing skis. Skis are wooden planks.
2. Friction helps us in writing on a chunk of paper. it’s unacceptable to write down and draw on oily or butter paper.
3. Friction helps us in lighting a match-stick by rubbing it along the rough surface on the edges of a matchbox. Igniting the match-stick rough surface is critical. As and when the rough surface on a matchbox becomes wet and smooth, the stick isn’t ignited.