Apple QuickTime movie | 1995-07-13 | 6.8 MB | 512x276 | 30fps | 1 minute, 16 seconds
Transcription: If rotational inertia is analogous to mass, what is the rotational analog of force? Here Ringo opens a massive door by pushing as far from the hinges as possible and his push is perpendicular to the door. The same principle applies when you use a wrench You grasp the wrench as far out as possible and push or pull perpendicular to the wrench. We call R-perp, the perpendicular distance from the pivotal point to the line of force, the lever arm. The product of force and lever arm is the twisting force, or torque. Torque equals F times R-perp. Torque is the rotational analog of force. Note how mak ...
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