Tehetetlenségi

Tehetetlenségi is a Hungarian adjective derived from tehetetlenség, meaning inertia or the resistance to changes in motion. It is used in physics to describe concepts related to inertia, and in everyday language to convey a general sense of resistance to change. A common technical term is tehetetlenségi nyomaték, typically translated as the moment of inertia, which quantifies how mass is distributed with respect to a chosen axis.

In rotational dynamics, tehetetlenségi nyomaték I measures an object’s resistance to angular acceleration about a given axis. For a point mass m at distance r from the axis, I = m r^2. For a system of particles, I = sum m_i r_i^2. For a continuous body, I = ∫ r^2 dm. The unit is kilogram square metres (kg·m^2). The rotational equation of motion is τ = I α, where τ is torque and α is angular acceleration.

The concept also embodies linear inertia, commonly described in physics by Newton’s first law: an object at rest stays at rest, and an object in motion stays in motion unless acted upon by a net external force. In everyday language, tehetetlenségi can describe a system’s or organization’s resistance to change, as in non-technical discussions of processes that persist despite efforts to alter them.

Etymology and usage: tehetetlenségi comes from tehetetlenség with the adjectival suffix -i. The root tehetetlen means unable or powerless, linking the term to the broader idea of resistance to change.

See also tehetetlenség, nyomaték, inertia (in Hungarian, inercia), Newton’s laws.