AQA AS Physics Definitions LATEST UPDATE
Specific charge
the charge to mass ratio or charge in coulombs divided by the mass in kilograms
Isotope
a nucleus with the same number of protons but different number of neutrons
Hadron
a particle that experiences the strong nuclear force. Composite particles made of either
qqq (baryons) or q anti-q (baryon)
Antimatter
Particles with the same mass but opposite charge
Photoelectric effect
the emission of electrons from metal surfaces by light of an appropriate frequency
Photon
a discrete packet/quantum of electromagnetic energy
Work function
the minimum energy required for an electron to escape from the surface of the metal
Threshold frequency
the minimum frequency of a photon required to release electrons from the surface of a
metal
Electron volt
the energy given to an electron when it passes through a potential difference of 1 V
Energy Level
Allowed/discrete energy of an atom or electron in an atom
Ionisation energy of an atom
the minimum energy required to remove an electron from an atom in its ground state
Excitation energy
the energy required to move an electron from a lower energy level to a higher energy
level
Specific charge
the charge to mass ratio or charge in coulombs divided by the mass in kilograms
Isotope
a nucleus with the same number of protons but different number of neutrons
Hadron
a particle that experiences the strong nuclear force. Composite particles made of either
qqq (baryons) or q anti-q (baryon)
Antimatter
Particles with the same mass but opposite charge
Photoelectric effect
the emission of electrons from metal surfaces by light of an appropriate frequency
Photon
a discrete packet/quantum of electromagnetic energy
Work function
the minimum energy required for an electron to escape from the surface of the metal
Threshold frequency
the minimum frequency of a photon required to release electrons from the surface of a
metal
Electron volt
the energy given to an electron when it passes through a potential difference of 1 V
Energy Level
Allowed/discrete energy of an atom or electron in an atom
Ionisation energy of an atom
the minimum energy required to remove an electron from an atom in its ground state
Excitation energy
the energy required to move an electron from a lower energy level to a higher energy
level
