8
ENERGY
Energy
What is energy?
Energy is how things change and move.
It is all around us and takes all sorts of forms.
Potential
Nuclear
Chemical
types of energy
Motion
Electrical
Gravitational
Light
Heat
Renewable Energy
- can be replenished
- wind power from wind mills
- hydro power from turbines in dams
- solar energy from the sun
Renewable
Non-Renewable
- cannot be re-created, takes millions of years to produce
- once used they are gone
- coal
- gas
Non-renewable
Heat Energy
Also called Thermal energy.
- everything in the universe is made of molecules.
- atoms-molecules-matter
- When the temperature rises in matter, the molecules vibrate.
- the hotter the temperature, the more vibration and the more thermal energy is created.
Nuclear Energy
Chemical Energy
Chemical Energy is released when bonds form in a chemical reaction, often producing heat as a by-product.
It is also called potential chemical energy as it is stored energy- waiting to be released.
Kinetic Energy
In physics, the kinetic energy of an object is the energy that it possesses due to its motion.
Kinetic Energy is found in movement. An airplane flying or a meteor plummeting each have kinetic energy.
Even the tiniest things have kinetic energy, like atoms vibrating when they are hot or when they transmit sound waves. Electricity is the kinetic energy of flowing electrons between atoms.
Gravitational Energy
First what is gravity?
It is the invisible force that pulls us toward the centre of the earth.
Gravitational energy is also known as gravitational potential (having the capacity to become something else) energy.
When a ball is thrown up in the air - the point where the ball stops and then starts to drop is the potential point. As the ball drops it increases speed- this is the gravitational energy.
Electrical Energy
Light Energy
The potential for light to perform is called light energy. It is the only form of energy that we can actually see. it is formed through chemical, radiation and mechanical means.
It can be converted into other types of energy.
- Light travels at the speeds of 300,000km per second
- The sunlight we see here on Earth left the sun 10minutes before
- During photosynthesis plants use light energy to convert into chemical energy
- UV lights are often used by forensic scientists to see details that are not seen by the naked eye.
- Although humans cannot see UV light, some insects have the ability to see it.
- Optics is the study of light.
- The speed of light changes when traveling through different objects.
- Light is a type of electromagnetic energy.
- Light is made of tiny photons which contain lots of energy.
- The intensity of photons is dependent upon the amount of energy they contain.
- Space is dark because light is only visible when it has an object of which to bounce off.
- Light energy is always moving and can therefore not be stored.
- Light is also called electromagnetic radiation when speaking of light other than visible light.
- Of all the forms of radiation and light on the electromagnetic spectrum, humans can only visibly see a very small amount of light.
- The reason we see different colors of light is because each color has a different wavelength.