A train rounds an unbanked circular bend of radius 30 m at a speed of `54 km//h` The mass of the train is `10^(6)` kg What provides the centripetal force required for this purpose ? The engine or the rails ? What is the angle of banking required to prevent out the rails ?

Explanation

The centripetal force is provided by the lateral thrust by the rail on the flanges of the wheels. By the Third Law, the train exerts an equal and opposite thrust on the rail causing its wear and tear.
Angle of banking ` = tan^(-1) ( (v^2)/(R g)) = tan^(-1) ( (15 xx 15)/(30 xx 10)) = 37^@`