tööenergiat

tööenergiat is the Estonian term for work energy, describing the energy transferred to or from an object via a force acting over a distance. In physics, work is defined as the dot product of a force vector and the displacement vector of the point of application of the force: W = F·d cos θ, where θ is the angle between the force and displacement. Positive work increases an object's kinetic or potential energy, while negative work decreases it.

The Work–Energy Theorem relates the total work done on an object to its change in kinetic energy: ΔK = K₂ – K₁ = W_total. For a single object moving along a straight line with constant mass, kinetic energy K equals (1/2)mv². Potential energy represents stored mechanical energy, such as gravitational potential U = mgh, where h is height above a reference level, and elastic potential energy in a spring U = (1/2)kx².

In addition to mechanical work, energy transfer can occur through heat, electricity, and other non‑mechanical means, but work remains the primary way forces change the state of motion or configuration of a physical system. Because work and energy are scalar quantities, they are often used in engineering, physics, and environmental science to evaluate system efficiency, power costs, and resource usage. The conservation of mechanical energy applies to frictionless or conservative‑force systems, stating that the sum of kinetic and potential energies remains constant when only conservative forces act.