Energy - Energy Transfers Flashcards
what are the 8 energy stores
kinetic, thermal, chemical, GPE, nuclear, electrostatic, elastic and magnetic
what is a system
an object or a group of objects
what is a closed system
neither matter or energy can enter or leave
how is energy transferred mechanically
an object moving due to a force acting on it
how is energy transferred electrically
a charge moving through a pd
how is energy transferred by heating and radiation
hotter to colder object
through waves
what is the conservation of energy principle
energy can be transferred, stored or dissipated but never created or destroyed
what is the equation for kinetic energy
(J) 1/2 mass (kg) x velocity^2 (m/s)
what is the equation for gravitational potential energy
(J) mass(Kg) x height(M) x gravitational field strength (N/KG)
for a falling object with no air resistance, what is the transfer of energy
energy lost from gpe = energy gained in kinetic store
how do u transfer energy to the elastic potential store of an object
stretch it or squash it
what is the equation for elastic potential energy
(J) 1/2 spring constant (N/M) x extention^2 (m)
what is specific heat capacity
amount of energy needed to raise the temperature of 1kg of a substance by 1 degree
how much energy do you need to heat 1 kg of water by 1 degree
4200j
what is the equation for change in thermal energy
mass (KG) x SHC(j/kgc) x temp change
what is power
rate of energy transfer
what equation can be used to calculate power
energy transferred/ time (S)
what is power measure in
Watts (w)
what is one watt equivalent to in joules
one joule per second
what is conduction
the process in which vibrating particles transfer energy to neighbouring particles
why do hot particles vibrate more
they have more energy transferred to their connected stores
how does heat transfer from one object to another
particles collide which causes energy to be transferred between the particles kinetic stores
in which state of matter does conduction usually occur
solid
what is thermal conductivity
a measure of how quickly energy is transferred through a material. materials with a high thermal conductivity transfer energy between their particles quickly.
