P2 Flashcards
How is enegry transferred?
It is transferred between stores, it is never used up
What are the different energy stores?
- Thermal
- Kinetic
- Gravitational potential
- Elastic
- Chemical
- Nuclear
- Electromagnetic
- Electrostatic
What is the conservation of energy principle?
- Energy can be transferred usefully, stored or dissipated, but can never be created or destroyed
- ENERGY TRANSFERRED(J) = power (W) x time (s)
What are the two types of energy resources?
Renewable and Non-ren
ewable
What are renewable resources?
- Energy resouces that can be used and does not run out
- Isnt as reliable as non rewable
What are non renewable resources?
Resources that will run out one day
How do power stations use steam to drive a turbine?
1)As the fossil fuel burns, the water is heated
2)The water then boils to form steam, whcih then moves and turns a turbine
3)The turbine is connected to an electrical generator, which generates a potential difference accross a wire by spinning a magnet near to the wire
4)The current produced by the generator flows through the national grid
What are some examples of renewable sources?
- Solar cells- expensive but no environmental damage
- Biofuels-made from plants and waste
- Hydroelectricity- Building dams and flooding valleys
- Tidal barrages-using the sun and moons on gravity
What is kinetic energy?
Energy of moving objects
What is chemical energy?
Anything with stored energy that can be released by a chemical reaction
What is elastic energy?
Energy stored in squashed, stretched ot twisted materials, rubber brands and springs are examples
What is elastic energy?
Energy stored in squashed, stretched ot twisted materials, rubber brands and springs are examples
What is magnetic energy?
Energy stored in two magnets attractring or repelling
What is electrostatic energy?
Energy stored in two electrical charges either attracting or repelling
What is nuclear energy?
Energy stored in the nucleus of atom
What is thermal energy?
Energy stored in objects that give off heat
What is thermal energy?
Energy stored in objects that give off heat
What is Gravitational Potential energy?
The energy stored by an object liftes up against the force of gravity.
What is power?
- The amount of energy transferred per second measured in watts(W)
- power(W)= Energy transferred(J) / time(s)
- Power is also the rate at which work is done
- power(W) = work done(J) / time(s)
What is conduction?
- Vibrating particles transfering energy to neighbouring particles
- When heating a metal, as end of metal gets heated, energy is transferred to metals kinetic energy store of particles at that end
- This causes particles to vibrate faster and collide with neighbouring particles more with energy
What is thermal conduction?
How well an object transfers energy by conduction
What is convection?
- The process by which heat is transferred by movement of a heated liquid
- Because partivles aren’t fixed, once heated up they gain kinetic enrgy and all particles move around faster
- more energetic particles to move away from warmer region towards colder region
What is work done?
Work done is used with force to move an object an object by a certain distance
What is conservation of energy?
Energy can be transferred usefully, stored or dissapated, but can never be created or destroyed
How is nuclear energy obtained?
It is obtained via nuclear reactionns such as nuclear fission in nuclear power stations
What is alternating current?
- AC current is when the direction of current flow swaps back and forth
- Gotten when using alternating potential difference
What is direct current?
- DC current is when the charge flows in one direction
- it is either positive or negative
What are the wires in a plug?
- Live wire-Brown wire which alternates potential difference(230V)
- Neutral wire-Blue wire which completes circuit by carrying awy current(0V)
- Earth wire-Green and yellow wire which doesnt usually carry current but stops appliance becoming live(0V)
- Each wire is made from copper to conduct electricity well
- They are also coated in a layer of plastic to be able to differ them and for safety
