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Comparison Rotation & Translation

There are many analogies between translational and rotational motion of bodies, which make it easier to remember certain physical relationships. For example, velocity in linear motion corresponds to angular velocity in circular motion. The table below lists the most important analogies, including their physical quantities.

QuantityTranslationRotationDescription
Displacement\( s \)\( \varphi \)Angle
Velocity\( v = \frac{\mathrm{d}s}{\mathrm{d}t} \)\( \omega = \frac{\mathrm{d}\varphi}{\mathrm{d}t} \)Angular velocity
Acceleration\( a = \frac{\mathrm{d}v}{\mathrm{d}t} \)\( \alpha = \frac{\mathrm{d}\omega}{\mathrm{d}t} \)Angular acceleration
Mass / Inertia\( m \)\( I \)Moment of inertia
Momentum\( p = mv \)\( L = I\omega \)Angular momentum
Force / Torque\( \vec{F} = \frac{\mathrm{d}\vec{p}}{\mathrm{d}t} = m\vec{a} \)\( \vec{D} = \frac{\mathrm{d}\vec{L}}{\mathrm{d}t} = I\vec{\alpha} \)Torque
Motion equation\( s = \frac{1}{2}a t^2 + v_0 t + s_0 \)\( \varphi = \frac{1}{2}\alpha t^2 + \omega t + \varphi_0 \)Angular motion equation
Kinetic energy\( E_\mathrm{kin} = \frac{1}{2}mv^2 \)\( E_\mathrm{rot} = \frac{1}{2}I\omega^2 \)Rotational energy

Let me know if you'd like to integrate this into a document or use another table style!

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