Energy
Energy is the ability to do work.
The types of energy:
1. Electrical
2. Mechanical
3. Chemical
4. Thermal
5. Nuclear
Law of conservation of energy – Energy cannot be created or destroyed. It can only be
transferred from one form to another or from one object to another.
Potential energy is the energy stored in an object due to its position.
Kinetic energy is the energy an object has due to its movement.
o Ek = ½ x m x v2
Types of Kinetic energy
1. Electrical – Energy due to the movement of electrons.
2. Mechanical - Energy stored in moving objects that is the product of its mass and
velocity.
3. Radiant (electromagnetic) energy – Energy that is released into space from stars.
Includes Radio waves, microwaves, and x-rays.
4. Thermal energy – heat energy that is responsible for an object's temperature.
5. Sound energy – The movement of energy through substances that causes vibrations.
Types of potential energy
, 1. Elastic energy – refers to the energy stored as a result of applying a force to deform
an object.
2. Chemical energy – the energy stored in bonds of chemical compounds.
3. Gravitational energy – The energy a physical object of mass has due to its attraction
to another massive object of mass.
4. Nuclear energy – The energy in the nucleus of an atom. It is the energy released when
an atom is split, or two atoms are combined.
Energy sources
Main energy sources (8)
1. Fossil fuels
2. Nuclear
3. Wind
4. Sun
5. Geothermal
6. Hydroelectricity
7. Hydrogen
8. Biomass
Sun
- Advantages: renewable, clean
- Disadvantages: expensive to set up, dependent on weather, requires a lot of space
Winds
- Advantages: clean, free, high-energy output