Nettokraftarbeit

Nettokraftarbeit, in physics, is the work done by the net force acting on an object as it moves along a path. It is the line integral of the net force along the trajectory: W_net = ∫ F_net · dr, where F_net is the vector sum of all forces acting on the object and dr is the differential displacement along the path. This quantity represents the total energy transferred to or from the object by the forces.

According to the work–energy theorem, the net work changes the object's kinetic energy: W_net = ΔK = (1/2) m v^2 − (1/2) m v0^2, with m being the mass and v and v0 the final and initial speeds. Therefore nettokraftarbeit is a direct link between force interactions and motion, independent of the specific path taken, once the initial and final speeds are known.

Conservative and non-conservative forces determine how nettokraftarbeit depends on position. For purely conservative forces, the net work depends only on initial and final positions and equals the negative change in potential energy, W_cons = −ΔU. In a closed path under conservative forces, the net work is zero. When non-conservative forces (such as friction or drag) are present, W_net includes energy dissipated or added as heat or other forms, and the value generally depends on the path taken.

In practice, nettokraftarbeit is used to analyze mechanical systems by relating force interactions to changes in kinetic energy, with common examples including gravity, normal forces, friction, and drag. It provides a unifying framework for understanding how energy is transferred during motion.