This is in some range acceptable but if it's too much it will derail. If you introduce tilt into railway itself you decrease amount of train tilting. I am somewhat not satisfied with the explanation of accepted answer. I found no mention of normal force which is key to understanding this situation. In this case, normal reaction is orthogonal to centrifugal force , so it has no effect on it. Whatever slipping is prevented, is prevented solely by friction. In this case, a component of normal reaction acts inwards, opposite to centrifugal force.
This helps in reducing wearing of tyres, as friction would reduce. Also it would help prevent toppling, as torque of the body about line joining the outerwheels reduces. Sign up to join this community.
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Nitesh Jaiswal 30th Oct, A car while taking a turn performs circular motion. If the road is level or horizontal road , the necessary centripetal force is the force of static friction between the car tyres and the road surface. The friction depends upon the nature of the surfaces in contact and the presence of oil and water on the road. If the friction id inadequate, a speeding car may skid off the road. Since the friction changes with circumstances, it cannot be relied upon to provide the necessary centripetal force.
Moreover, friction results in fast wear and tear of the tyres. To avoid the risk of skidding as well as to reduce the wear and tear of the car tyres, the road surface at a bend is tilted inward, i. This is called banking of road. Equilibrium 1. Is it possible What is the Why is a A man carrying Why a wrench During pregnancy, woman Rotational Dynamics 2.
A fan with If the earth Suppose that only Explain why spokes A dancer girl Elasticity 1. A rigid, lighter Why bridges are Explain which one Periodic Motion Simple Harmonic Motion 1. If a pendulum On what factors What are the A pendulum clock If we incline the track until it is nearly vertical, we see that there a huge friction force would be required but only a tiny normal force is available.
As this would not be possible without gluing the tires to the road, this situation would result in the bus sliding downwards towards the center of the track. Now increase the speed of the bus to produce a centripetal acceleration. Newton's law implies that there must be a centripetal friction force producing this acceleration. As the speed increases, we will eventually reach a point when the friction force required is too large and the bus will slide outwards on the track.
To avoid sliding outwards, we can increase the bank on the road. This increases the normal force and decreases the friction force, making it less likely that sliding will occur. For any given speed, there is some angle that exactly cancels the friction force, so that all the force is normal force. This is a very safe driving situation, as no sliding is possible, even in very slippery road conditions. On the real track , the bank angle increases as the bus drives higher.
This allows the driver to select the correct incline angle to minimize sliding risk. We can also show the forces in components or as total vectors as we change the bank angle and bus speed.
While this simple point mass model allows us to understand how banking the road can help with the problem of sliding, it does not tell us anything about rolling of the vehicle, because point masses can't rotate.
We thus need a rigid body model to investigate roll. Higher speed and a smaller radius of curvature on a circular track allows higher bank angles, as in the photo below. Image credit: Daimler Global Media Site full-sized image , original rotated image. We now use a single rigid body model for the bus and we will do everything in 2D. Below we see a front-on diagram of the bus, with the inside of the track to the left. If we turn on the free body diagram , then we see that the weight of the bus is supported by two forces, one on each wheel.
If the slope becomes too steep, then the normal force on the up-slope wheel reverses direction, indicating that it is holding the wheel down onto the road. Physically this cannot happen, so at this point the bus would tip over.
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