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Joules are units used to measure both work done and energy transfer. One joule represents the amount of work done when a force equal to 1 newton moves an object a distance of 1 meter in the direction of the force.
The capacity to do work or transfer heat.
Calorie: A unit of energy commonly used in nutrition, equal to approximately 4.184 joules.
The exertion of force over a distance resulting in the displacement or movement of an object.