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Kinetic Energy✓ verified

Physics / Mechanics · Translational kinetic energy

Parameters

InputSymbolUnitDefaultDescription
massmkg1.0Mass of the body
velocityvm/s1.0Linear speed of the body
OutputSymbolUnitDescription
kinetic_energyKEJKinetic energy

The science & history

Understanding the Parameters

Derivation (Approaching a Proof)

Newton’s second law: $F = m a = m\,dv/dt$. Power delivered by the force is $P = F v = m v\,dv/dt$. Energy gained over a path is the integral of power:

$$KE = \int P\,dt = \int_0^{v} m v\,dv = \frac{1}{2} m v^{2},$$

starting from rest. Equivalently, work $W = \int F\,ds = \int m a\,ds = \int m v\,dv$ yields the same result (work–energy theorem). Rotational counterpart: Rotational Kinetic Energy.

History

The $mv^{2}$ form emerged in 17th–18th century vis viva debates (Leibniz, Huygens); the factor $\tfrac12$ and the modern kinetic-energy name solidified with 19th-century energy conservation (Thomson, Rankine, Helmholtz).

Related Concepts: Potential Energy, Work Constant Force, Momentum, Rotational Kinetic Energy, Power

Notes: Registry calculator kinetic-energy (unverified). Non-relativistic; for $v$ not near $c$. Scalar speed form (not $\tfrac12 m\mathbf{v}\cdot\mathbf{v}$ written out).

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