The units commonly used for energy are:
1. Joules (J): Joules are the standard unit of energy in the International System of Units (SI). For example, the energy stored in a battery or the energy required to lift an object can be measured in joules.
2. Kilogram meters squared per second squared (kg·m²/s²): This unit is also known as a joule (J). It is derived from the base units of mass, length, and time. It represents the energy transferred or converted in a system.
3. Kilojoules (kJ): Kilojoules are a larger unit of energy equivalent to 1000 joules. They are commonly used to express the energy content of food or the energy output of engines.
Newton (N) and meters per second squared (m/s²) are not units of energy but rather units of force and acceleration, respectively.
