Question

What is banking of roads? Why banking is necessary for a curved road?

Answer 1

Banking of road is the process of raising outer edges of a road over its inner edge through certain angle.

Necessity of banking of road-

When a vehicle moves on a curved horizontal surface, friction force between wheels and road provides the necessary centripetal force. But friction force is enough sometimes like during rain as road is oily. Road should be made through then but it cause wear & tear of tyres. When centripetal force is less the vehicle skid. To eliminator this difficulty, roads are banked. When road is banked, the horizontal component of normal reaction provides necessary centripetal force required for circular motion.

So, roads are banked to provide necessary centripetal force.