Memory definitions Flashcards
Nuclear model
This model describes the atom as having a small positively charged core surrounded by negatively charged particles called electrons
Mass defect
The difference between the mass of an intact nucleus and the sum of the masses of the individual nucleons of which it is made
Strong nuclear force
One of the four fundamental forces; the strong nuclear force acts over small distances in the nucleus to hold the nucleons together against the repulsive electrostatic forces exerted between the protons.
Binding energy
The mechanical work that must be done against the forces holding a nucleus together to disassemble it into component parts.
Natural radioactive decay
the process by which the nucleus of an unstable atom loses energy by emitting radiation, including alpha particles, beta particles, gamma rays and electrons without artificial stimulus to do so.
Radiation
the emission of energy as electromagnetic waves or as moving subatomic particles, especially high-energy particles, which cause ionisation.
Ionisation
The process by which an atom or molecule acquires a negative or positive charge by gaining or losing electrons.
Alpha radiation
The composite particle consisting of two protons and two neutrons tightly bounded together; emitted from the nucleus of some radionuclides.
Beta negative radiation
A type of radioactive decay in wh8ich an energetic electron and associated antineutrino are emitted from an atomic nucleus.
Beta positive decay
A type of radioactive decay in which an energetic positron and associated neutrino are emitted from the nucleus.
Gamma radiation
Extremely high frequency electromagnetic radiation (high frequency photons) emitted form the nucleus of some radionuclides.
Nuclear fusion
A nuclear reaction in which two or more atomic nuclei combine to form one or more different, heavier atomic nuclei and subatomic particles
Nuclear fission
The process in which a large unstable nucleus splits, forming two (or more) smaller more stable nuclei and releasing neutrons and energy.
Artificial transmutation
The process in which an isotope is intentionally caused to change by nuclear processes into an isotope of another element (distinct from natural radioactivity).
Half life
the time taken for half of the atoms in a sample of the material to undergo radioactive decay
Electric charge
a physical property of an object that causes it to experience a force when placed in an electric field.
Law of Conservation of electric charge
The total electric charge of an isolated system remains constant, regardless of charges within the system.
Law of Electrostatic Attraction
Opposites attract, likes repel
Electric current
The rate of movement of electric charge carriers from one part of a conductor to another
Electromotive force
a difference in potential that tends to give rise to an electric current
Electrical potential difference
The change in potential energy per unit charge between two defined points in a circuit
Resistance
The ration of voltage applied to the electric current that flows through it
Ohmic resistor
A resistor that behaves according to Ohm’s law
Non-ohmic resistor
A resistor that does not behave according to Ohm’s law
Kirchhoff’s current law
At any node in an electric circuit, electric charge is conserved such that the sum of the electric currents flowing into a node is equal to the sum of the electric currents flowing out of that node
Kirchhoff’s voltage law
The energy inputs in a circuit equal the energy output form loads in the circuit such that the directed sum of the electrical potential difference around any closed network is zero.
Power
The rate at which work is done or the rate at which energy is transferred or transformed.
Power dissipation
A measure of the rate at which energy is lost from an electrical circuit.
