An electric motor exerts a force of 125N on an object causing it to move horizontally at a constant speed of 0.4ms-1.The output power is L125 ×0.4=50WFriction in the motor bearings and electrical resistance of the motor wires means that some electrical energy supplied is wasted. If the motor is supplied with 150W then the wasted power is 100W.
Electric Motor
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Specification: AQA Physics (7407), AS-level, 3.4.1.7 Work, energy and power. Topic: Work, Energy and Power.
Key terms in this lesson
- Elastic limit
- The point beyond which a material no longer returns to its original length when the deforming force is removed.
- Limit of proportionality
- The point beyond which the extension of a material is no longer directly proportional to the applied force.
More in Work, Energy and Power
- Electrical Power
- Engine Power
- Drag Force
- Machines and Work
- Pulley System
- Efficiency
- Improving Efficiency
- Renewable Energy - Wind Power
All 21 lessons in Work, Energy and Power · All AQA AS-level Physics topics