keywords Flashcards
(17 cards)
what is a closed system?
system that experiences no net change in it’s total energy when energy transfers occur within it
what is conservation of energy?
law that energy can be transferred, stored or dissipated but never destroyed
what is elastic potential energy?
energy stored in stretched or compressed object depends on how stiff it is and how much it’s stretched or squashed
what is efficiency?
the ratio of useful output energy transfer to total energy input
what are fossil fuels?
coal, oil and gas
what is gravitational potential energy
store of energy all raised matter has. proportional to the mass of an object the distance that it’s risen and the gravitational strength
what is a joule?
unit used for energy. equal to work done when a force of one newton acts over a distance of a metere
what is kinetic energy?
store of energy all matter has. proportional to object’s mass and square of it’s velocity
what is power?
rate at which energy is transferred, or work is done
what is a renewable energy resource?
energy resource that can replenished whilst being used
what is specific heat capacity?
amount of energy required to raise the temperature of a 1kg substance by 1 degree
what is spring constant?
measure of a spring’s stiffness greater the value, greater the force needed to stretch or compress
what is a system?
single or group of objects
what is thermal conductivity?
higher vale for object higher the rate of transfer via conduction
what is waste energy?
energy that isn’t used in the system
what is watt?
unit of power. 1 watt=1 joule of work being done per second
what is work done?
energy transferred when a force acts over another distance
