Physics, Energy Mind Map

One of the most important concept in energy is "Principle of Conservation of Energy"

1. Energy cannot be created or destroyed
2. Energy can only be converted from one form to another
3. Total amount of energy in any system is always the same.

Some examples of energy converting from one form to the other are:

1. Ball dropping [Gravitational potential -> kinetic -> heat + sound -> ... ...]
   
2. Light bulb [Electrical -> heat + light ]

Work done is a measure of energy. A couple of important idea to take note.

1. A force must be applied to an object
2. Object must move some distance IN THE DIRECTION OF FORCE

If the object do not move. There is NO work done.
Object must MOVE in THE DIRECTION OF FORCE to have work done.

Efficiency is a ratio of the amount of USEFUL energy output of a system with respect to the TOTAL energy input. It is often expressed as a percentage.

Power is the rate of work done. Example : If A and B use the same energy to do the same work and A completes the work faster than B. We can say that A have higher power than B.