MATTER AND ENERGY
2.5 - Energy
All physical and chemical changes
(section 2.3) are accompanied by changes in energy. Here
are a few common processes and their associated energy changes:
- eating an orange results in a release of energy.
- burning charcoal in a summer BBQ results in a release of energy.
- ice melting in your thirst quenching drink uses energy.
- boiling water in a kettle uses energy.
What is ENERGY?
Energy exists in a variety of forms. Energy associated with chemical
reactions is evolved as heat. Other forms of energy are:
- light energy
- sound energy
- electrical energy
- mechanical energy
- chemical energy
Although there are various forms of energy, they can be interconverted
from one form to another.
The chemical energy stored in the battery
converted to electrical energy
useful light energy emitted from a flashlight
and to less useful heat energy