What is the SI unit of energy?

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Multiple Choice

What is the SI unit of energy?

Energy is the capacity to do work, and the SI unit used for energy is the joule. Work equals force times distance, so the unit for work (and energy) is newton-metre. Since a newton times a metre is defined as one joule, 1 joule is the amount of energy transferred when a 1-newton force moves an object 1 metre. The other units describe different things: watt is power (energy per second), Newton is a unit of force, and Pascal is a unit of pressure. For example, lifting a 2-newton weight by 0.5 metres uses 1 joule of energy (2 N × 0.5 m = 1 J).

Energy is the capacity to do work, and the SI unit used for energy is the joule. Work equals force times distance, so the unit for work (and energy) is newton-metre. Since a newton times a metre is defined as one joule, 1 joule is the amount of energy transferred when a 1-newton force moves an object 1 metre. The other units describe different things: watt is power (energy per second), Newton is a unit of force, and Pascal is a unit of pressure. For example, lifting a 2-newton weight by 0.5 metres uses 1 joule of energy (2 N × 0.5 m = 1 J).

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