What is the SI unit of energy?

What is the SI unit of energy?

• A. Joules
• B. Watts
• C. Newtons
• D. Volts

Answer: (A)

Energy is the capacity to do work. In the SI system, the unit of energy is the joule. A joule is defined as the work done when a force of one newton moves an object one meter, so 1 J = 1 N·m. This links energy directly to how much work is performed, whether you’re lifting, accelerating, or heating. Power, on the other hand, is the rate of energy transfer, measured in watts (1 W = 1 J/s). The other units shown represent force (newtons) and electrical potential difference (volts), which describe different physical quantities, not energy. For example, kinetic energy is measured in joules as E_k = 1/2 m v^2, and energy can also be expressed in larger units like kilojoules or kilowatt-hours, but the SI unit remains the joule.

Energy is the capacity to do work. In the SI system, the unit of energy is the joule. A joule is defined as the work done when a force of one newton moves an object one meter, so 1 J = 1 N·m. This links energy directly to how much work is performed, whether you’re lifting, accelerating, or heating. Power, on the other hand, is the rate of energy transfer, measured in watts (1 W = 1 J/s). The other units shown represent force (newtons) and electrical potential difference (volts), which describe different physical quantities, not energy. For example, kinetic energy is measured in joules as E_k = 1/2 m v^2, and energy can also be expressed in larger units like kilojoules or kilowatt-hours, but the SI unit remains the joule.