When we push a huge rock, there is no transfer of muscular energy to the stationary rock. Also, there is no loss of energy because muscular energy is transferred into heat energy, which causes our body to become hot. From the conservation of energy we know that energy can neither be created nor destroyed, it can only be transformed from one form to another.
Energy is a conserved quantity and the law of conservation of energy states that energy can neither be created nor destroyed but can only be converted from one form to another. The SI unit of energy is Joule.
Transfer of energy
The movement of energy from one location to another is known as energy transfer. There are energy transfers going on all the time – whenever a system changes there is a change in the way some or all of the energy is stored.
Following are the four ways through which energy can be transferred:
- Mechanically – By the action of force
- Electrically – Electrically
- By Radiation – By Light waves or Sound waves
- By Heating – By conduction, convection, or radiation
The process which results in the energy changing from one form to another is known as energy transformation. While energy can be transformed or transferred, the total amount of energy does not change – this is called energy conservation.