Energy resources and energy transfers Flashcards
what are the eight types of energy stores?
1- kinetic
2- thermal
3- chemical
4- GPE
5- elastic potential
6- electrostatic
7- magnetic
8- nuclear
what happens in kinetic?
anything moving has energy in its kinetic energy store
what happens in thermal?
any object- the hotter the more energy it has in it’s store
what happens in chemical?
anything that can release energy by a chemical reaction e.g food and fuels
what happens in GPE?
anything that is in a gradational field (anything that can fall)
what happens in elastic potential?
anything stitched like springs and rubber bands
what happens in electrostatic?
two charges that attract or repel
what happens in magnetic?
two magnets that attract or repel
what happens in nuclear?
atomic nuclei releases energy from this store in nuclear reactions
what are the four main ways that energy can be transferred between?
1- mechanically
2- electrically
3- by heating
4- by radiation
what happens in mechanically?
an object moving due to a force acting on it e.g push or pull
what happens in electrically?
a charge moving through a potential difference e.g charges moving through a circuit
what happens in heating?
energy transferred from a hotter object to a cooler object
what happens in radiation?
energy transferred by light/sound waves
what is the principle of conservation of energy?
energy cannot be created or destroyed but it can be transferred from one store to another
what is efficiency defined as?
efficiency= useful energy output/total energy input
x100
what are the 3 ways energy can be transferred by heating?
radiation, conduction and convection
what is thermal radiation?
the transfer of energy by heating by infrared electromagnetic waves
what is conduction?
the main form of energy transfer by heating in solids
what is convection?
the main form of energy transfer by heating in liquids and gases
what does thermal radiation involve?
emission of electromagnetic waves
what can thermal radiation also be called as?
infrared radiation, consists of electromagnetic waves of different frequencies .
what do all objects continually do?
emit and absorb infrared radiation
if an object is hotter than its surrounding what happens?
it emits more radiations that it abosrbs as it cools down
if an object is cooler than its surrounding what happens?
it absorbs more radiation that it emits as it warms up
is a solid is heated what happens?
the particles are held tightly together. when one particle vibrates, it collides with other particles nearby.
definition of thermal conduction?
the process where vibrating particles transfer energy from their kinetic energy store to the kinetic energy stores of neighbouring particles.
definition of convection?
convection occurs when the more energetic particles move from the hotter region to the cooler region and transfer energy only in liquids and gases.
