GED Physics summary

Physics Chapter 9

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