AQA AS Physics Definitions Exam Questions and Answers 100% Pass

AQA AS Physics Definitions Exam Questions and Answers 100% Pass Specific charge - Answer- the charge to mass ratio or charge in coulombs divided by the mass in kilograms Isotope - Answer- a nucleus with the same number of protons but different number of neutrons Hadron - Answer- a particle that experiences the strong nuclear force. Composite particles made of either qqq (baryons) or q anti-q (baryon) Antimatter - Answer- Particles with the same mass but opposite charge Photoelectric effect - Answer- the emission of electrons from metal surfaces by light of an appropriate frequency Photon - Answer- a discrete packet/quantum of electromagnetic energy Work function - Answer- the minimum energy required for an electron to escape from the surface of the metal Threshold frequency - Answer- the minimum frequency of a photon required to release electrons from the surface of a metal Electron volt - Answer- the energy given to an electron when it passes through a potential difference of 1 V Energy Level - Answer- Allowed/discrete energy of an atom or electron in an atom Ionisation energy of an atom - Answer- the minimum energy required to remove an electron from an atom in its ground state Excitation energy - Answer- the energy required to move an electron from a lower energy level to a higher energy level Line spectra - Answer- the characteristic wavelengths of light produced by individual excited atoms Longitudinal waves - Answer- direction of oscillation is parallel to the direction of wave travel. Wave travels with series compressions and rarefactions. Transverse waves - Answer- direction of oscillation is perpendicular to the direction of wave travel with peaks and troughs. Electromagnetic wave - Answer- a transverse wave, consisting of a changing magnetic field at right angles to a changing electric field Amplitude - Answer- the maximum displacement from the equilibrium position Frequency - Answer- the number of oscillations per second Wavelength - Answer- the shortest distance between two consecutive particles in a wave which are in phase Wave speed - Answer- the speed of energy transfer through the medium Diffraction - Answer- Diffraction is the spreading out of a wave as it passes through an aperture/around an obstacle. Polarised waves - Answer- electromagnetic waves where the oscillati