Hooke S Law — the NEET Physics formula with its derivation, variables, validity constraints and worked solver.
Hooke's Law Valid for small deformations within the elastic limit of the material. Assume small deviations from equilibrium in a potential energy well. Approximate the potential energy curve as a parabola (Taylor expansion around minimum). The derivative of potential energy (Force) becomes linear with respect to displacement. Material must stay within its elastic limit (yield strength). Spring must not be compressed to solid length or stretched to breakage. Believing the law applies universally to all deformations (plastic deformation violates it). Confusing the restoring force (exerted by the spring, F = -kx) with the applied force (exerted on the spring, F = kx). Assuming k is unitless (it is N/m).