Physics

To calculate the total work done by gravity during the entire motion, we need to consider the two parts of the motion: the horizontal motion and the vertical lifting.

 

Work done during horizontal motion:

Since gravity acts vertically and the motion is horizontal, the angle between the direction of gravity and the displacement is 90° (). Therefore, no work is done by gravity during the horizontal motion.

 

Work done during vertical motion (lifting the box):

When the box is lifted vertically by 3 meters, gravity does negative work because it acts downward while the displacement is upward. The work done by gravity is calculated as:

 

Where:

,

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