You're working for FedEx lifting boxes onto a truck from the ground nearby. There's a ramp attached to the end of the truck that
some other people are using to walk boxes up into it. Who is doing more work on the boxes (assuming they're identical): the people walking the boxes up, or you lifting the boxes straight into the truck?
In simple words, the work done by all the parties is actually same. This case could be understood by using the theories of potential energy. The work performed should be measured as equivalent as the work done is equal to the increase in gravitational energy potential and is the same with all cases as the possible change in energy based on truck height or elevation and regardless of direction.
