A-Level Physics OCR A Definitions UPDATED QUESTIONS AND A+ GRADED ANSWERS

A-Level Physics OCR A Definitions UPDATED QUESTIONS AND A+ GRADED ANSWERS acceleration - ANS Rate of change of velocity. Vector quantity Acceleration of free fall - ANS Rate of change of velocity of object falling in a gravitational field air resistance - ANS Drag/resistive force experienced by objects moving through air Ammeter - ANS Device used to measure electric current-placed in series (ideally 0 resistance) ampère - ANS Base SI unit of electric current, A, current flowing in two parallel wires in a vacuum 1m apart such that atractive force 2.0*10-7 per metre length of wire between them amplitude - ANS Max displacement from equlibrium point of a particle in a wave angle of incidence - ANS Angle between direction of travel of incident ray and normal angle of reflection - ANS angle between direction of travel of reflected ray and normal anion - ANS negatively charged ion -attracted to anode antiparallel - ANS Same line but opposite directions antiphase - ANS Particles ocillating where one reaches max displ. whilst other reaches min displ. Archimedes' Principle - ANS Upthrust on a object in fluid equals weight of fluid it displaces average speed - ANS Rate of change of distance in time average velocity - ANS rate of change of displacement in time base unit - ANS one of 7 units that form building blocks of SI measurements battery - ANS collection of cells that transfer chemical energy to electrical energy braking distance - ANS distance travelled by vehicle from time brakes applied to full stop breaking strength - ANS stress value at point of fracture-breaking force diveded by cross sectional area brittle - ANS lack of ability of plasticity capacitor - ANS compenent that stores charge, consists of 2 plates seperated by an insulator cathode - ANS negatively charge electrode cation - ANS posiively charge ion that is attracted to cathode cell - ANS device that transfers chemical energy into electrical energy centre of gravity - ANS imaginary point at which entire weight of object appears to act centre of mass - ANS point through which any fexternal force applied makes straight line motion but no rotation charge carrier - ANS particle with charge that moves through material to form electric current closed system - ANS isolated system that has no interaction with surroundings coherence - ANS two waves that are coherent have same constant phase difference compression - ANS a region in which medium is denser or has higher pressure than surrounding medium compressive deformation - ANS change in shape of object due to compressive forces