Friction has enormous influence on the motion of an object. Friction is a kind of resistive force which slows down the motion of a body. Though friction creates many problems in our daily lives, it plays a vital role for movement and vehicle operaration. Here discuss about tyre’s surface, smoothness of road and role of friction for controlling motion.

Tyre’s surface


Driving vehicles is possible because of the friction between the tyres and the road surface. The friction force between the tyres and the road depends on condition of the tyres and surface of the road. It also depends on the weight of the vehicle. The tyre’s rubber surface is designed with treads i.e. grooves or teeth. The tyre surface is up and down due to these grooves. If the tyre is new, these grooves are distinct; as a result the force of friction between the tyre and the road is maximum. When the tyre becomes old, their grooves are worn out and the surface becomes flat. As a result the frictional force between the tyre and the mad decreased mostly. Say, what inconvenience may arise due to this.

Smoothness of road

The smoothness of road has a great impact on the motion of a body. When the mad is smooth, movement of vehicles on the road becomes easier and the journey becomes comfortable. As the road becomes smoother, the resistive force of friction becomes lesser. The magnitude of the frictional force between the car’s tyre and the road depends on the smoothness of the tyre as well as on the smoothness of the mad. Many types of problems arise when amount of the frictional force is decreased largely. So, the road should not be too smooth. If the mad is too smooth, it is not possible to stop the car within a certain distance in spite of applying brake. The friction is important for the motion of a car. If the mad is too smooth, the necessary reaction force is not produced. The amount of the frictional force is largely reduced when the road is too smooth, as a result the car will not be able to move forward. So, the smoothness of the mad will be such that it can supply the necessary frictional force.

Controlling motion and braking force

The speed of the vehicle has to increase or decrease according to the necessity at the time of vehicle movement. That is, we have to control the motion of a vehicle. Brake is such an arrangement, which controls the speed of the car or rotation of the wheels according to the necessity by increasing the friction. With this it is possible to halt a vehicle in a certain place. When the driver applies the brakes, the shoe or pad made of asbestos press the metallic disc on the wheel. The friction between the pad and disc slows down the wheel’s speed. As a result, the velocity of a car decreases.