NCEA Level 3 Modern Physics

Created by

Tom Nguyen

Cards (43)

Bohr's model of the atom proposed that electrons orbit the nucleus in specific energy levels or shells.
Electron transitions between different energy levels result in the emission or absorption of photons with specific wavelengths.
The energy levels are quantized, meaning that electrons can only exist at specific energies.
Ionisation 
The ability of nuclear radiation to take an electron off an atom, making it an ion.
Balmer Series
Visible Light produced by excited Hydrogen electrons.
Lyman Series 
Ultraviolet light produced by excited Hydrogen electrons
Paschen Series 
Infared Light produced by excited Hydrogen electrons.
Binding Energy
The energy required to break a nucleus into its constituent protons and neutrons
Binding energy per nucleon
Energy required to separate a nucleus into its nucleons divided by number of nucleons
Energy Level 
Fixed quantities of energy which an electron can have in an atom.
Fission 
Nuclear reaction where one big nucleus splits into two smaller nuclei.
Frequency 
The number of waves passing a point per second. (Hz)
Fusion 
Nuclear reaction joining two smaller nuclei to make one bigger nucleus.
Ground State 
Lowest energy level an electron can have when orbiting an atom. (n=1)
Electromagnetic Spectrum 
All of the frequencies or wavelengths of electromagnetic radiation
Energy Absorption 
The amount of energy taken in by an electron when excited.
Mass deficit/defect 
The difference between the sum of the masses of the individual nucleons forming a nucleus and the actual mass of that nucleus
Photoelectric Effect 
Effect where metal surface releases electrons when struck by photons.
Photon 
A particle of electromagnetic radiation that carries energy
Radiation 
Emission of energy as particles (α,β) or waves (γ)
Threshold Frequency 
The smallest amount of frequency that is required to release electrons from metal surface.
Work Function Φ
Minimum energy needed for electrons to escape a metal surface during photoelectric effect.
Emission line spectrum 
a collection of narrow bands of light produced by atoms of a given element releasing energy
Absorption line spectrum 
Spectral lines given out/absorbed by low pressure gases when they are excited
Nuclear Force 
The attractive force between the nucleons in the nucleus; happens as a result of the strong interaction between quarks.
Electron-Volt 
Amount of Ek gained by one electron as it is accelerated through a potential difference of one volt. J → eV = ÷ 1.6 x 10 ^-19
E = ∆mc²
The mass of an object includes its energy- changing the energy of an object also changes its mass.
(fo) Threshold Frequency
The minimum frequency of photons that cause electrons to be emitted from a metal surface
(Φ) Work Function
Minimum energy needed for electrons to escape a metal surface during photoelectric effect
gamma radiation 
High-energy radiation emitted by the nuclei of radioactive atoms.
E=mc^2 
E is binding energy (release nucleons). m is mass deficit
Radioactive Decay
Release of nuclear particles and energy from unstable atomic nuclei.
Alpha emission 
Release of alpha particle from unstable nucleus(a 2+ helium ion or a helium nucleus)
Beta emission 
An high-energy electron which is ejected from the nucleus; this release causes a neutron to convert into a proton
Unstable nucleus 
A nucleus that spontaneously undergoes change, which involves emission of radiation from the nucleus.
Stable nucleus 
Nucleus is stable if contains correct ratio of protons and neutrons and it stays together
Alpha particle 
The nucleus of a helium atom (two protons and two neutrons) emitted as radiation from a decaying heavy nucleus
Beta particle 
High-energy electron emitted as ionizing radiation from a decaying nucleus
electron volt (eV) 
The energy gained by an electron moving across a potential difference of one volt; equivalent to 1.60 x 10-19 Joules
ground state 
Energy state of an atom with electrons at the lowest energy state possible for that atom