ENS 303 Lecture Notes - Lecture 12: Mechanical Advantage, Firstclass, Weak Interaction
2 Feb 2019
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Document Summary
Lever: a single machine that can amplify an applied force (effort) by converting it into torque. All movements will occur via the coordinated arrangement of bony levers. Odd shaped bones like scapula, vertebrae and cranium provide leverage. Long bones of arms and legs suited to generate maximum advantage. Level made of three parts: axis, effort, resistance. Effort arm: distance between the effort and axis. Resistance arm: span between the resistance and axis. Three types of levers: some will produce a great force over a short distance while others produce weak force over long distance. Great on force, poor for rom and speed. Advantage afforded by this type of lever will depend greatly on the length of its effort arm compared to its resistance arm. Length of effort arm determines the amount of effort required. Leverage: the mechanical advantage of a force to move an object. Muscles gain leverage by using bones as levers.
