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Question
Answer in brief:
Why are curved roads banked?
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Solution
- When a car makes a turn, it moves in a circular manner. The necessary centripetal force is the static friction force between the car tyres and the road surface if the road is level (or horizontal).
- The amount of friction is determined by the nature of the surfaces that come into contact, as well as the presence of oil and water on the road. If the friction is insufficient, a speeding car may skid off the road. Because friction varies depending on the situation, it cannot be relied upon to generate the required centripetal force. Furthermore, friction causes rapid tyre wear and tear.
- To avoid the risk of sliding and the wear and tear on car tyres, the road surface at a bend is tilted inward, i.e., the outer side of the road is raised over the inner side. This is known as road banking. On a banked road, the result of the normal reaction and gravitational force can serve as the required centripetal force. As a result, any car can be driven safely on such a banked curve at an ideal speed without relying on friction. As a result, at a bend, a road should be correctly banked.
- The angle of banking is the angle of inclination of a banked road's surface at its end with the horizontal.
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