AQA A LEVEL PHYSICS PAPER 1 MAY 2023 QUESTION PAPER(7408/1) Genuine And Well Elaborated For Best Scores

AQA A LEVEL PHYSICS PAPER 1 MAY 2023 QUESTION PAPER(7408/1) Genuine And Well Elaborated For Best Scores What is meant by work function (2) - correct answerMinimum energy required by an electron to escape from (1) a metal surface (1) What is meant by ionisation energy? (2) - correct answerMinimum energy required to remove an electron from an atom (1) from the ground state (1) Why do emitted electrons have a kinetic energy that varies up to a maximum value? (4) - correct answerEnergy of a photon is fixed/constant (1) Energy is required for electrons to overcome work function ø (1) Electrons deeper into/below the surface of the metal require more energy to overcome work function and therefore have less KE(1) Maximum KE = Energy of photon - work function ø (1) Explain how (bright ring) diagram is evidence of the wave-particle duality of electrons? - correct answerDiffraction pattern maxima/minima (bright and dark areas) (1) Diffraction is a property of waves- proves wave-behaviour of electrons (1) What is meant by the ground state? - correct answerThe lowest energy state of an atom Explain the difference between excitation and ionisation (2) - correct answerAn electron receives a discrete amount of energy for BOTH (1) Excitation promotes an electron to a higher energy level Ionisation is when an electron receives enough energy to leave the atom Explain why only photons of certain frequencies cause excitation (4) - correct answerdiscrete energy levels (1) Electrons need to absorb a DISCRETE amount of energy to move to a higher energy level (1) Photons need to have a certain frequency to provide this energy, because E=hf (1) interaction is a 1:1 reaction all of the photon's energy is absorbed (1) Explain how excitation takes place in a fluorescent tube - correct answerElectrons flow through the tube to the applied PD causing a current to flow (1) Electrons collide with mercury atoms in the tube (1) This raises electrons in the mercury atom to a higher energy level (1) What is the purpose of coating in a fluorescent tube? - correct answerUV/ High energy photons emitted from mercury atoms when the electrons in the atom de-excite (1) High energy photons absorbed by the coating (1) Coating emits photons in the visible spectrum (1) What happens when annihilation occurs? (2) - correct answerparticle and an anti-particle collide and cease to exist (1) Their mass is released as energy in the form of a pair of gamma photons (1) How does the strong nuclear force between two nucleons vary with the separation of the nucleons? (3) - correct answerrepulsive at 0.5 fm (1) attractive from 0.5 to 3 fm (1) above 3 fm, force 0 (1) What is meant by monochromatic light - correct answerlight of a single frequency