Question

Railway tracks are banked on curves, so that 

(a) necessary centrifugal force may be obtained from the horizontal component of the weight of the train

(b) no frictional force may be produced between the tracks and the wheels of the train 

(c) necessary centripetal force may be obtained from the horizontal component of the weight of the train

(d) the train may not fall down inwards

Answer 1

(c) necessary centripetal force may be obtained from the horizontal component of the weight of the train

The banking on curves maintains the train to stay on the track by providing the necessary centripetal force in the form of the horizontal component of the weight of the train. The raised track imparts the centripetal force which is required to move round the curve safely.