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In physics, rotatum is the derivative of torque with respect to time. Expressed as an equation, rotatum Ρ is:

\vec P = \frac{d \vec \tau}{dt}

where τ is torque and \frac{\mathrm{d}}{\mathrm{d}t} is the derivative with respect to time t.

The term rotatum is not universally recognized but is commonly used. this word derived from Latin word rotātus meaning to rotate.[citation needed] The units of rotatum are force times distance per time, or equivalently, mass times length squared per time cubed; in the SI unit system this is kilogram metre squared per second cubed (kg·m2/s3), or Newtons times meter per second (N·m/s).

Relation to other physical quantities

Newton's second law for angular motion says that:


where L is angular momentum, so if we combine the above two equations:


where I is moment of Inertia and \omega is angular velocity. If the moment of inertia isn't changing over time (i.e. it's constant), then:


which can also be written as:


where ς is Angular jerk.

See also