Question

2. A carte with a mass of 155 kg sitting on a flatbed truck which is moving at an acceleration of a = 2.78 m/s2. Suppose that the crate does not slip as the truck undergoes a displacement, whose magnitude is r = 111 m. Determine the total work done on the crate by all of the forces acting on it.

Answer 1

Given mass of the crate is

acceleration of the truck is

Thus, there acts an inertia force on the crate which is given by

  

Even though this force acts on the crate, the crate doesnot slip.

Thus, the net opposite force acting on the crate is same as this inertia force. Therefore,

Displacement of the truck is

Thus, the workdone on the crate is to stop the crate by net forces while travelling along this distance.

Therefore, workdone is given by