Final answer:
Work in physics is defined as the application of force over a distance, with the formula W = Fd cos θ, which simplifies to W = Fd when force and displacement are parallel.
Step-by-step explanation:
In physics, work is defined as the application of a force over a distance. The formula for work when a constant force is applied in one dimension is W = Fd cos θ, where W is work, F is the magnitude of the force, d is the distance over which the force is applied, and θ is the angle between the direction of force and displacement.
When the force is exerted parallel to the displacement, the angle θ is 0 degrees, and cos 0 is 1, simplifying the equation to W = Fd.
This equation expresses the relationship between work and the energy transfer in the form of work-energy theorem, stating that the net work on a system results in a change in kinetic energy, typically represented as W = Δ(1/2 mv²).