Conceptual Question on Work and Forces

Question

Alex and John are loading identical cabinets onto a truck. Alex lifts his cabinet straight up from the ground to the bed of the truck, whereas John slides his cabinet up a rough ramp to the truck. Which statement is correct about the work done on the cabinet−Earth system?

a. Alex and John do the same amount of work.

b. Alex does more work than John.     

c. John does more work than Alex.

d. None of those statements is necessarily true because the force of friction is unknown.

e. None of those statements is necessarily true because the angle of the incline is unknown.

I believe the answer should be (b) because the force of gravity is directed downwards, and it's parallel to the displacement of the cabinet (lifted vertically). Am. I correct?

Answer 1

In the absence of friction, both men do the same work regardless of incline angle.

In the real world, John will do more work as friction is a reality!