Energy Flashcards
What are energy forms
Different ways energy can appear
Eg heat light sound
What’s energy resources
Different ways of supplying a particular energy form
Eg coal oil wind
What’s kinetic energy
Energy possessed by a mass due to its speed
It moves
What’s gravitational potential energy
Energy possessed by a mass due to its height above the ground
It might happen
What’s the principle of conservation of energy
That energy can change from one form to another but can never be created or destroyed
What’s chemical energy
Energy stored within a substance which is released on burning
Eg coal oil battery’s food natural gas
What’s nuclear energy
Energy stored in the nucleus of an atom
Eg uranium plutonium
What Renewable energy
Energy that can be replaced by nature in less than a human lifetime, it will never run out
What is non renewable energy
Energy that will eventually run out
What’s solar cells
(renewable)
Convert sunlight directly into electricity
Joined together into arrays
What’s hydroelectric power stations do
(Renewable)
Water behind a high dam contains gravitational potential energy
The water falls through a pipe and gains kinetic energy
The fast flowing water on a turbine which then drives a generator
The output is electrical energy
How are tidal barrages created
When a dam is built across a river estuary
As the tide rises and falls every 12 hours water will flow through a gate
The moving water drives a turbine which will produce electrical energy
What does a wave machine do
It flats on the surface of the water and the “up and down” motion of the water is converted to rotary motion of a turbine generator to produce electricity
What’s a wind turbine do
(Renewable)
As the wind blows the large blade turns and drives a turbine
The turbine drives a generator which produces electricity
When alot of wind turbines group together it forms a wind farm
What does a geothermal power stations do
These use heat from hot rocks deep inside the earth
Cold water is passed down a pipe to the rocks
The rocks heat the water and the water is then pumped to the surface
Steam is generated to produce electricity
What does biomass do
Renewable
Fast growing trees are harvested
The wood is dried and turned into woodchips which are burned in power stations to produce electricity
There are many other forms of biomass such as oil from oil bearing seeds can be converted into biodiesel
What’s fossil fuels
Nom renewable
Oil, natural gas, coal, turf, lignite
Burned in power stations to produce steam which drives a turbine, to a generator to then producing electricity
What’s nuclear power
Non renewable
Large nuclei in a nuclear reactor are made into lighter nuclei with the release of large amounts of kinetic energy
This energy is used to produce steam which drives a turbine turns a generator and produces electricity
What’s an advantage of fossil fuels
Cheap to start
Large world reserves of coal
What’s a disadvantage of fossil fuels
Non renewable
All release carbon dioxide, contribute to global warming
Burning coal and oil causes acid rain
What’s an advantage of nuclear fuels
Doesn’t produce carbon dioxide
What’s a disadvantage of nuclear fuels
Waste products will remain dangerously radioactive for years
There’s no method to store these materials cheaply
Nuclear fission fuels are non renewable
What’s an advantage of wind farms
Renewable energy source
Cheap
Disadvantage of wind farms
Unreliable
Ugly
Very noisy
Hazardous to birds
Advantage to waves
Renewable energy source
Cheap
Disadvantage of waves
Unreliable
Ugly
Hazardous to shipping
Advantage to tides
Renewable energy source
Cheap
Disadvantage of tides
Navigation problems for shipping
Destruction of habitats
What’s work
The product of force and the distance moved in the direction of the force
It’s only done when a force causes movement
What’s the formula for work
Force × distance moved in the direction of the force
What’s energy
What is required to do work
Sometimes can be the amount of energy transferred
Work and energy are measured in joules(J)
What’s power
The rate of doing work
How much work a machine can do in a second
What’s the equation for power
Work done ÷ time taken
What’s efficency
The ratio of the useful output work to the total energy input
What’s the equation for efficency
Useful energy output÷total energy input
ALWAYS REMEMBER THE WEIGHT ON EARTH
1kg has a weight of 10N on earth
W=mg
What’s GPE equation
M×G×H
M-work done in raising a load
G-against the force of gravity
H-through the height
What’s the equation for kinetic energy
½×m×v²
Who’s the French scientist
Henri Becquerel
What did Henri becquerel discover
Rocks that gave out a strange radiation that could penetrative paper and fog photographic film, called radioactivity
Alpha
Beta
Gamma
What’s alpha
Particles that are helium nuclei containing 2 protons and 2 neutrons which are emitted by radioactive nuclei
+2 charge
High mass
Strong
Low penetrative power
What’s beta
Fast moving electron
Radioactive nucleus
-1 charge
Low mass
10% of the speed of light
Weak
What’s gamma
High energy electromagnetic wave
Radioactive nucleus
0 charge
Very weak
