First Class Lever Definition: the Fulcrum Is Located Between the Input Force and the Load

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First Class Lever Definition: the Fulcrum Is Located Between the Input Force and the Load

Lever Definition: a simple machine consisting of a bar that pivots at a fixed point, called a fulcrum First Class Lever Definition: The fulcrum is located between the input force and the load. First Class Lever Mechanical Advantage: Examples: • MA will be equal to, greater • See-saw than, or less than one, • Top of a Hammer to get depending on the location of out nails the fulcrum. • Oars • Scissors Lever Definition: a simple machine consisting of a bar that pivots at a fixed point, called a fulcrum Second Class Lever Definition: The load is located between the fulcrum and the input force. Second Class Lever Mechanical Advantage: Examples: • MA will be greater than 1 • Wheelbarrow • Bottle Opener Lever Definition: a simple machine consisting of a bar that pivots at a fixed point, called a fulcrum Third Class Lever Definition: The input force is between the fulcrum and the load. Third Class Lever Mechanical Advantage: Examples: • MA will be less than 1 • Lifting a dumbbell • Sweeping/Raking Leaves • Hammering in a nail Pulley Definition: A simple machine consisting of a grooved wheel that holds a rope or a cable; the load is attached to one end and an input force is applied to the other end. Fixed Pulley Definition: A pulley that is attached to something that does not move. Fixed Pulley Mechanical Advantage: Examples: • MA does not increase the force, • Elevator • MA = 1 • Flagpole Pulley Definition: A simple machine consisting of a grooved wheel that holds a rope or a cable; the load is attached to one end and an input force is applied to the other end. Movable Pulley Definition: A pulley that is attached to the object that is being moved Movable Pulley Mechanical Advantage: Examples: • Does not change the force’s direction. • Cable system on a boat • MA = 2 • Ski Lift • Bike lift to store in garage Pulley Definition: A simple machine consisting of a grooved wheel that holds a rope or a cable; the load is attached to one end and an input force is applied to the other end. Block and Tackle Definition: A pulley that is attached to the object that is being moved Block and Tackle Mechanical Advantage: • MA > 2 Examples: • Sails and rigging on a boat.

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