Q9 of 57 Page 95

Why do tires have a better grip of the road while going on a level road than while going on an incline?

On the level road the tyres have more grip on the road. It is because the full surface of tyres of car applies pressure on the surface of the road. The normal force is maximum in this case (mg; where m is the mass of the car, g is acceleration due to gravity). And hence the force of friction is also maximum. However, on the inclined surface, the total surface of the tyre will not touch the ground and only one component of the weight will press the ground i.e. mgcosθ. Hence the normal force will decrease and the frictional force will also decrease. This decreases the grip of car tyres on the inclined roads.


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