What is energy?
Energy is the ability to do work. Energy is anything that causes change, e.g. throwing a ball (moves position) or boiling water (changes state water-gas)
Work - using force to move an object a certain distance
The Principle of conservation of energy -
Energy cannot be created or destroyed , but can be converted from one form to another
Form of description energy -
- heat
- sound
- light
- kinetic
- potential
- nuclear
- chemical
- electrical
What is heat energy?
Particles in any material will vibrate more and more as their heat energy increases
What is sound energy?
Waves of energy that travel from place to place through materials . The particles of the material vibrate as the energy moves through the material
What is light energy?
Energy that comes from any light source , i.e. the sun , a lamp. It can travel through empty space.
What is kinetic energy ?
The energy an object has when moving
What is potential energy?
The energy stored in an object
What is nuclear energy?
The energy stored in the nucleus of an atom
What is chemical energy?
The energy stored in the bonds between molecules
What s electrical energy ?
The energy of certain particles when moving through electrical wires
What is the unit for energy ?
Joules ( J )
- energy is never used up - its converted to another form
Energy dissipation -
The heat energy from the light bulb is being dissipated. Energy dissipation is when energy changes form without preforming a useful functions
How do u work out the energy efficiency ?
Useful energy dived by imput energy times 100
What s renewable energy ?
An energy source that is infinite - it will never run out e.g. solar,wind,water,hydroelectric
What is non-renewable energy ?
An energy source that is finite - it will run out once used up it takes a long time to replenish the resource e.g.fossil fuels
Sustainability - energy
Sustainability - using resources wisely so that they don’t run out.
Reduce - reuse - recycle
- turn light off when not in use
- shower instead of a bath
- replace fossil fuels with renewable energy
Ethical issues with electricity generation and usage -
- fossil fuels cause global warming and acid rain
- wind farms can be unsightly , cause noise pollution
- nuclear power plants - accidents
