Question

A trolley of mass 200kg moves on a level track for a distance of 500m.if the resistance o track is 100N,find the work done in moving the trolly

Answer 1

Answer:

The initial momentum of the system (boy + trolley) is given as :

                                                                     

                                                                    

Now assume v' is the final velocity of the trolley with respect to the ground.

Then the final momentum will be :

                                                       

Conserving momentum :

                                            

or                                                      

The time taken by the boy is : 

                                                 

Hence the distance moved by the trolley is :