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Learn about mechanical advantage and the inclined plane, and investigate the quantitative aspects of mechanical advantage using interactive activities.
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Simple Machines: More Practice Inclined Plane
Simple Machines: More Practice Wheel and Axle
Simple Machines: More Practice Two levers!
Simple Machines: More Practice Inclined Plane
Simple Machines: More Practice Two levers again!
Mechanical Advantage and the Inclined Plane: Learning Goal The student will be able to explain the concept of mechanical advantage and investigate, in quantitative terms, the mechanical advantage of an inclined plane (C3.4, C2.6).
The Inclined Plane An inclined plane is simply a ramp that moves something horizontally as it moves vertically (and stairs may be included).
Load A load is a mass or weight that is being supported (and possibly being moved).
Load distance The load distance for the inclined plane is the vertical distance, or height, of the inclined plane.
Effort distance The effort distance is the total distance the load is being moved: the length of the inclined plane.
IMA The ideal mechanical advantage (or IMA) is defined as the ratio of the effort distance to the load distance:
IMA: Example A wheelchair ramp is 9.0 m long and has a vertical rise of 1.5 m. What is the ideal mechanical advantage of the ramp?
IMA: Example A wheelchair ramp is 9.0 m long and has a vertical rise of 1.5 m. What is the ideal mechanical advantage of the ramp?
IMA: Example A wheelchair ramp is 9.0 m long and has a vertical rise of 1.5 m. What is the ideal mechanical advantage of the ramp?
IMA: Example A wheelchair ramp is 9.0 m long and has a vertical rise of 1.5 m. What is the ideal mechanical advantage of the ramp?
Load force and effort force This mechanical advantage should also be reflected in the reduction of the force required to move the load: The load force is the weight of the load and the effort force is the force that is actually exerted to move the load.
AMA The actual mechanical advantage (or AMA) is defined as the ratio of the load force to the effort force:
AMA: Example A person exerts a force of 207 N to move herself and her wheelchair (total mass 95 kg) up the ramp. What was the actual mechanical advantage of the ramp?
AMA: Example A person exerts a force of 207 N to move herself and her wheelchair (total mass 95 kg) up the ramp. What was the actual mechanical advantage of the ramp?
AMA: Example A person exerts a force of 207 N to move herself and her wheelchair (total mass 95 kg) up the ramp. What was the actual mechanical advantage of the ramp?
AMA: Example A person exerts a force of 207 N to move herself and her wheelchair (total mass 95 kg) up the ramp. What was the actual mechanical advantage of the ramp?
Why is AMA lower than IMA? Actual mechanical advantage is always going to be lower than ideal mechanical advantage.
Why is AMA lower than IMA? Actual mechanical advantage is always going to be lower than ideal mechanical advantage. Why?
Why is AMA lower than IMA? Actual mechanical advantage is always going to be lower than ideal mechanical advantage. Why? Because the effort force also has to overcome friction.
Efficiency The percent efficiency of a machine is determined by:
Example For the wheelchair ramp in our example, the efficiency would be:
Example For the wheelchair ramp in our example, the efficiency would be:
More Practice Efficiency and Inclined Planes Lab Activity