If the direction an object is displaced is perpendicular to the direction of a force applied to it: No work is done. Positive work is done. Negative work is done.

If an object is displaced in a direction that is perpendicular to the force applied, no work is done on that object. This is because work is defined as the product of the force applied in the direction of displacement. When the angle between the force and the displacement is 90 degrees, the cosine of 90 degrees is zero, resulting in zero work: \( W = F \cdot d \cdot \cos(\theta) = 0 \). This principle can be observed in everyday situations! For example, when you carry a heavy bag while walking, the force of gravity acts downward, and your displacement moves horizontally. The vertical force does no work in the horizontal direction, showcasing how perpendicular forces and displacements impact the work done on objects.