James Joule was an English scientist born in Lancashire in 1818. He was the first scientist to realise that energy can come in many different forms.
- Sound Energy
- Light Energy
- Electrical Energy
- Chemical Energy
- Thermal Energy (better as known as heat)
- Kinetic Energy (better known as movement)
- Gravitational Potential Energy (the energy released when you jump off a wall, for example)
James Joule's work was rewarded by naming the units used to measure energy after him. Energy is measured in Joules (J) or more commonly kiloJoules (kJ) which is 1000 Joules.
1kJ = 1000J
A 100W light bulb releases 6000 Joules of energy every minute in the form of light and thermal energy. This can also be represented as 6 kJ of energy released every minute.