energy Flashcards
(41 cards)
energy stores
kinetic energy store, gravitational potential energy store, elastic potential energy store, electrostatic energy store, magnetic energy store, chemical potential energy store, nuclear energy store, thermal energy store
kinetic energy
the energy of a moving object
gravitational potential energy
the energy something gains when you lift it up, and which it loses when it falls
elastic potential energy
the energy of a stretched spring or elastic band
electrostatic energy
the energy due to the force of attraction (or repulsion) between two charges
magnetic energy
the energy due to the force of attraction (or repulsion) between two magnets
chemical potential energy
the energy contained in a chemical substance
nuclear energy
the energy contained within the nucleus of an atom
thermal energy
the energy something has due to its temperature (or state)
energy transfers
mechanically, electrically, heating, radiation
mechanically (energy transfer)
when a force acts on a body, energy can be transferred between two stores
electrically (energy transfer)
electricity can transfer energy from a power source, delivering it to components within a circuit
heating (energy transfer)
thermal energy can be transferred from place to place by the process of conduction, convection and thermal radiation
law of conservation of energy
energy is not created or destroyed, it can only be used or transferred from one store to another
efficiency formula
useful energy output/ total energy output x100
gravitational potential energy formula
mass x gravitational field strength x height
relationship between work done and energy transferred
work done=energy transferred
work done formula
work done=force x distance
what is power
power is the rate at which energy is transferred or the rate at which work is done
power formula
power= work/time
kinetic energy formula
ke= 1/2 x mass x velocity2
thermal conduction
the transfer of thermal energy through a substance by the vibration of the atoms within the substance
convection
the transfer of heat through fluids by the upward movement of warmer, less dense regions of fluid
radiation
the transfer of energy by infrared waves