AQA Physics paper 1 (100% correct answers)

Energy is transferred between stores correct answers Thermal, kinetic, gravitational potential, elastic potential, chemical, magnetic, electrostatic, nuclear Energy is transferred... correct answers Mechanically (by a force doing work), electrically (work done by moving charges), by heating or by radiation (like light or sound) When a system changes, energy is transferred correct answers It can be transferred into or away from the system, between objects in the system or between different types of energy stores. Closed systems are where neither matter nor energy can enter or leave. The net change in the total energy of a closed system is always 0 kinetic energy correct answers energy of motion - the greater an object's mass and the faster it is going, the more energy there will be in its kinetic energy store. Ek (j) = 1/2m(kg)v(m/s) squared Raised objects store energy in gravitational potential energy stores correct answers lifting an object in a gravitational field requires work, causing an energy transfer to the the GPE store of the object. Ep(j) = m(kg)g(n/kg)h(m) Falling objects transfer energy correct answers Falling objects transfer energy from its GPE store to its kinetic energy store. When there's no air resistance, energy lost from the GPE store = energy gained in the kinetic energy store Stretching transfers energy to elastic potential energy stores correct answers As long as the limit of proportionality has not been exceeded, Ee (j) = 1/2 k (N/m) e (m) squared specific heat capacity correct answers the energy required to raise the temperature of one gram of a substance by one degree Celsius. E (j) = m(kg) c(j/kgdegree) theta (degrees Celsius) Conservation of energy principle correct answers Energy can be transferred but can never be created of destroyed Dissipated energy correct answers energy used up in a system, typically lost due to work done by friction, 'wasted energy' Phone energy correct answers When you use the phone, energy is usefully transferred from the chemical energy store of the battery in the phone, but some of this energy is dissipated to thermal energy Closed system energy transfer correct answers A cold spoon is dropped into hot soup in an insulated flask, which is then sealed. Energy is transferred from the thermal energy store of the soup to the useless thermal energy of the spoon Power correct answers The rate at which work is done (watts). P(w) = E(j) / t(s)