A train of mass 20 000 Kg freewheels down a straight incline of angle 10 degrees at constant speed 15 m/s in that the gravitational effect is cancelled by friction and air resistance.
It then comes to a level stretch, the friction and air resistance remaining the same. Find how far it travels before coming to rest.
The train then starts moving again, by switching on the engine, and after a modest speed (value being immaterial here) comes to an upward incline of x degrees. Friction and air resistance still remain at their previous value.
Find in terms of x, the engine force P needed to maintain a constant speed up the incline. Sketch a graph of P against x. Is any interpretation possible for negative x?
PS: The coefficient of friction 'model' is not used in this question. The frictional force is taken as constant, along with air resistance. g = force du to gravity = 10