An overview of work, energy, and power—their definitions and significance in everyday life and scientific context.

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Illustrative examples show when work is done: a pebble moves, a trolley is pulled, or a book lifted, highlighting force and displacement.

Two conditions for work: (1) Force acts on the object. (2) Object must be displaced. Without these, no work is done.

Work can be positive or negative depending on the direction of the force relative to displacement. Example: lifting a box involves positive work.

Energy is the capacity to do work. It exists in many forms and is measured in joules (J).

Energy comes in various forms: mechanical, heat, chemical, electrical, and light. Each has specific applications.

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Examples: A moving car, falling coconut, or flying ball. All demonstrate kinetic energy due to their motion.

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Energy in stretched rubber bands, compressed springs, and raised objects represents potential energy.

Energy cannot be created or destroyed; it only changes forms. Total energy remains constant.

Energy can transform from one form to another, like kinetic to potential and vice versa, with no loss.

The work done equals the change in kinetic energy, highlighting energy's role in motion.

Power is the rate of doing work, measured in watts (W). It indicates how fast work is done.

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Illustrative examples show how different agents, like machines and people, do work at varying rates, showing power diversity.