Physics

To calculate the work done by gravity during the entire process, we need to consider both the lifting and falling parts of the motion.

 

Work done while lifting

When the object is lifted, a force of 120 N is applied over a distance of 5 meters. The work done by the lifting force is:

 

Work done by gravity during lifting

During the lifting process, gravity opposes the motion, so the work done by gravity is negative:

 

Work done by gravity during the fall

When the object falls back to its original position, gravity acts in the same direction as the motion, so the work done by gravity is positive. The distance fallen is the same 5 meters, and the gravitational force is 100 N: