AQA GCSE Triple Science – Physics Latest 2023 Graded A+

AQA GCSE Triple Science – Physics Latest 2023 Graded A+ Name 8 energy stores Thermal Kinetic Gravitational potential Elastic potential Chemical Magnetic Electrostatic Nuclear What are the four ways that energy is transferred? Mechanically, electrically, by heating, by radiation What is a closed system? Neither energy nor matter can enter or leave. The net change in the total energy of a closed system is always zero. What does work done mean? Energy transferred What happens to an object's g.p.e. store and kinetic energy when it falls? The object's gravitational potential energy store is transferred to its kinetic energy store. What is the equation for kinetic energy? Kinetic energy = 0.5 x mass x (velocity)^2 What is the equation for gravitational potential energy? Gravitational potential energy = mass x gravitational field strength x height What is specific heat capacity? The amount of energy needed to raise the temperature of 1kg of a substance by 1 degree C. What is the conservation of energy principle? Energy can be transferred usefully, stored or dissipated, but can never be created or destroyed Describe the transfer of energy in a closed system for a cold spoon and hot soup. Assume the flask is a perfect thermal insulator. Energy is transferred from the thermal energy store of the soup to the useless thermal energy store of the spoon (causing the soup to cool down slightly). Energy transfers have occurred within the system, but no energy has left the system - so the net change in energy is zero. What is power? The rate of energy transfer or the rate of doing work What is energy measured in? Joules (J) What is power measured in? watts What is one watt? 1 joule of energy transferred per second What are the two equations for calculating power? Power(W) = energy transferred(J) / time(s) Power(W) = work done(J) / time(s) What is conduction? conduction is the process where vibrating particles transfer energy to neighbouring particles How does conduction happen? The thermal energy in the object causes the particles to vibrate more and collide with each other. This causes the energy to be transferred between particles' kinetic energy stores In what states does convection occur? Liquid and gas What is convection? Convection is where energetic particles move away from hotter to cooler regions How does convection happen? Unlike in solids, the particles are able to move. When you heat a region of a gas or liquid, the particles move faster and the space between individual particles increases. This causes the density to decrease. The warmer regions will rise above the cooler, denser regions, and the process repeats. What do lubricants do? Reduce the friction between objects' surfaces when they move. They are usually liquids so they can flow easily between objects and coat them. How do you prevent energy losses through heating in a house? Have thick walls made from a material with low thermal conductivity Use thermal insulation Give four examples of thermal insulation and what