Rated A
Current - -Rate of flow of charge
Resistance - -The ratio of a components
potential difference to its current
Coulomb - -The amount of charge passing
a point when a current of 1A flows for 1s
Volt - -The potential difference across a
component when 1 joule of energy is used to
Potential difference - -The work done per move a coulomb of charge through a component
unit charge in moving a small point positive
charge between two points
Ohm's Law - -Provided that the physical
conditions remain the same, the current through
Threshold Voltage for a Diode - -The an ohmic conductor is directly proportional to the
voltage at which a current will begin to flow at, potential difference across it
assumed to be +0.6V if not stated
Ohmic conductor - -A material that follows
Reverse Bias - -When very little currency Ohm's law when physical components remain the
can flow in the reverse direction of a diode same
Variable Resistor - -Can be used to Diodes - -Components made from semi
change the current through a circuit can also be conductors that only allow current to flow in one
called a rheostat direction
NTC Thermistor - -(A type of Resistivity - -The resistance of a 1m length
semiconductor) that has decreasing resistance of wire with a 1m^2 cross sectional area
when its temperature increases - negative
temperature coefficient
Superconductor - -A material that has zero
resistivity when it is cooled below its critical
Transitional Temperature - -The critical temperature
temperature at and below which a
superconductor has zero resistivity
Critical Temperature - -The temperature
below which a material will have zero resistance
Semiconductor - -A group of materials and will become a superconductor
which conduct electricity (not as well as metals),
when their temperature rises they can release
more charge carriers and their resistance Power - -The rate of transfer of energy
decreases
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, AQA A level Physics Paper 1 Test Questions and Answers
Rated A
EMF - -The work done in moving a unit being emitted
charge through a battery
Photons - -Virtual particles that are discrete
Lost Volts - -Work done per unit charge in packets of energy
overcoming the internal resistance within a
battery
Antiparticle - -Opposite in charge to the
particle but have the same rest mass and rest
Terminal PD - -The potential difference energy
between the two terminals of the power supply
PET Scan - -Positron Emission
Potential Divider - -A circuit with a constant Tomography
voltage source and more than one resistor
connected in series that can be used to vary the
output voltage Rest Energy - -The amount of energy that
would be produced if all of a particle's mass was
transformed into energy
Threshold Frequency - -The minimum
frequency that must be incident on the surface of
a metal for the emission of photoelectrons to Fundamental Particle - -A particle that
occur cannot be split up into smaller particles
Electromagnetic Force - -A fundamental Stopping Potential - -The work done by the
force that causes interactions between charged potential difference in stopping the fastest moving
particules. Virtual photons are the exchange electrons
particles
Electron Volt - -The kinetic energy that an
Gravitational Force - -A fundamental force electron has after being accelerated from rest
which causes attraction between objects with a through a potential difference of 1 volt
force proportional to their mass
1 eV = - -1.6x10^-19 Joules
Strong Nuclear Force - -A fundamental
force with a short range which is attractive
between 0.5-3 fm and repulsive between 0-0.5fm Ground State - -The lowest energy level
that an electron can occupy in an atom (n=1)
Alpha Decay - -Occurs in nuclei of 82
protons or more that consists of an alpha particle Excitation - -When an electron gains the
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