physics- energy efficiency calculations Flashcards
what is total energy measured in?
jules
J
what is an effeciency of a device always between?
0 and 1
what is the law of conservation of energy?
Energy cannot be created or destroyed but is transferred from 1 store to another.
kenetic energy
the energy of a moving object
anything that is moving
chemical energy
anything with stored energy which can be released by a chemical reaction
food ,bateries, fuel
Thermal energy
Is produced when a rise in temp causes atoms and molecules to move faster and collide with each other.
hot water, hot radiator
elastic
the energy stored when an abject is stretched or squashed
bungee cord, clockwork toy
light
any luminous gives off
fire,light bulb
sound
any noise given off
radio, talking
electrical
anything that has a current flowing has electrical energy
power lines, power socket
neuclear
released only from neuclear reactions
neuclear bombs
energy can remain in the same store for millions of years or just a fraction of a second
there are energy transfers going on all the time whenever the system changes there is a change in the way some or all of the energy is stored
what is the energy transfer from a car with lights off
start-chemical transfer to-sound, thermal ,kinetic
what is energy ifficency?
is a way of saying how good a device is at transferring energy as a useful output
what is neuclear energy
spliting of uranium atoms- a process called fission. this generates heat to produce steam which is used by a turbine generator to generate electricity.
