Studied by 6 peopleAcceleration
change in v per unit t
Acceleration of free fall
Acceleration of an object only acted on by force of gravity
Accurate
Measurement obtained using calibrated instruments correctly
Accuracy
How close to the true value
Alpha radiation
Particle consisting of 2 P's and 2 N's
Amplitude
Max displacement of oscillating particle from equilibrium position
Annihilation
Particle and antiparticle meet, destroy eachother and emit radiation
Antibaryon
Hadron w/ 3 quarks
Antimatter
Antiparticles with same quantum values but opposite charge to corresponding particles
Antinode
Fixed point on stationary wave where amplitude is maximum
Atomic number Z
Number of P's in atom nucleus
Baryon
Hadron w/ 3 quarks
Base units
Units that define the SI system:
Kg Amp S M
Beta radiation
when B- or B+ particles are emitted following decay of a neutron-rich or proton-rich nucleus
Braking distance
Distance travelled by vehicle in time taken to stop
Breaking stress/Ultimate tensile stress
Tensile stress needed to break a solid material
Brittle
Snaps without bending or stretching when subject to stress
Centre of mass
Point through which a single force on the body has no turning affect
Charge carriers
Charged particles that move through substance when PD applied across it
Kirchoff's 1st Law
Current passing through 2 or more components in series is the same through each component
At a junction the total current in = total current out
Kirchoff's 2 Law
2 or more components in series - total PD across all the components is = to sum of the PD's across each component
Sum of emf's around complete loop = sum of PD's around the loop
Coherent
Constant phase difference and same frequency
Conservation rules
Rule that: Baryon no Lepton no Charge Energy Momentum
always conserved in interactions
When is strangeness conserved?
Strong interactions
How are strange particles created?
Strong interactions
How to strange particles decay?
Weak interactions
Couple
Pair of equal and opposite forces acting upon the same body but not along the same line
Critical angle
The angle of incidence of a light ray must exceed this angle for total internal reflection to occur
Critical temperature
Temperature at or below which a superconducting material has zero resistivity
Cycle
Interval for an oscillating particle from a certain displacement and velocity to the next time the particle has identical displacement and velocity
de Broglie hypothesis
Matter particles have a wave-like nature
de Broglie wavelength
Wavelength of a matter particle
deexcitation
process by which atom loses energy by photon emission as electron moves to lower energy level - inner shell
denisty
mass per unit volume for substance
diffraction
spreading out of waves that pass through gap or near edge
diffraction grating
plate with close parallel slits on it
dispersion
splitting of beam of white light into colours by prism
displacement
distance in a given direction from equilibrium position
drag force
force of fluid resistance on an object moving through fluid
ductile
stretches easily without breaking
efficiency
ratio of useful energy transferred to energy supplied to it
output power/input power
elastic limit
point beyond which wire is permanently stretched
elasticity
property of solid that allows it to regain shape after being deformed
electrolysis
process of electrical conduction in a solution or molten substance due to charged ions moving to oppositely charged electrode
electrolyte
solution that conducts electricity
electromagnetic interaction
force or interaction between 2 charged objects
electromagnetic wave
wavepacket or photon consisting of transverse electic and magnetic waves in phase and at right angle to eachother
emf
electrical energy per unit charge produced inside electrical source
electron volt
work done when an electron is moved through a PD of 1V
endoscope
optical fibre device used to see inside cavities
energy
capacity to do work
energy levels
discrete energy levels that electrons take in shells of atom
equilibrium
object in rest or constant motion
error bar
uncertainty representation on a graph
error of measurement
uncertainty of a measurement
excitation
process in which atom absorbs energy without becoming ionised when electron moves from inner shell to higher energy level in outer shell
first harmonic
pattern of stationary waves on a string when it oscillates at lowest possible frequency
fluroescence
emission of visible photons after atoms deexcite
frequency
number of cycles of a wave that pass a point per second
friction
force opposing the motion of a surface that moves or tries to move across another surface
gamma radiation
high energy photons emitted by unstable nuclei or produced in particle annihilations
gravitational field strength
force per unit mass on small object in gravitational field
ground state
lowest energy state of an atom
hadron
particles and anti that can interact through the strong interaction
Hooke's Law
the extension of a spring is proportional to the force applied to it
inertia
resistance of an object to a change of its motion
interference
formation of points of cancellation and reinforcement where two coherent waves pass through eachother
internal resistance
resistance inside the source of electrical energy - loss of PD per unit current in the source when current passes through it
ion
charged atom
ionisation
process of creating ions
isotopes
atoms of the same element with a different number of neutrons and the same number of protons
kaon
meson that has a strange quark and another quark
kinetic energy
energy of an object due to its motion
laser
produces coherent, parallel beam of monochromatic light
lepton
particles that cannot interact through the strong interation
light-dependent resistor
resistance decreases in light
limit of proportionality
limit beyond which - if a wire or spring is stretched - the extension is no longer proportional to the force applied
longitudinal waves
waves with particles that oscillate parallel to the direction of propagation of the wave
mass
measure of inertia of the motion of an object
matter waves
wave-like behaviour of particles
meson
hadron w/ quark and antiquark pair
modal dispersion
lengthening of a light pulse as it travels along optical fibre due to continual total internal reflection of waves meaning some rays travel longer distance than others in fibre
moment
about a point is the force x perpendicular distance from the line of action of the force to the point
muon
negatively charged lepton with a greater rest mass than the electron
negative temperature coefficient
resistance of a semiconductor decreases when its temperature is increased
neutrino
uncharged lepton with a lower rest mass than the electron
Newton's 1st Law of Motion
object remains at rest or in uniform motion unless acted upon by a resultant force
Newton's 2nd Law of Motion
rate of change of momentum of an object is proportional to the resultant force applied to it
node
fixed point on a stationary wave where displacement is zero
nucleon
N or P in nucleus
nucleon number
number of P's or N's in the nucleus
nuclide
type of nucleus with a particular number of P's and N's
Ohm's Law
PD across a metallic conductor is proportional to the current - if physical conditions remain constant
optical fibre
thin, flexible transparent fibre used to carry light pulses from one end to another
pair production
gamma photon changed in a particle and corresponding antiparticle
path difference
difference in the distances from two coherent sources to an interference fringe
period
time for one complete cycle of a wave to pass a point
phase difference
the fraction of a cycle between the oscillations of 2 oscillating particles - measured in radians
photoelectric effect
emission of electrons from metal surface when surface is hit with light with photons of frequency greater than threshold frequency
photon
packet or 'quantum' of electromagnetic waves
Note 
Flashcard (24)