Particles And Waves Flashcards
What makes up hadrons ?
Quarks
What are baryons made up of ?
3 quarks eg protons,neutrons
Mesons are made up of ?
2 quarks (a quark and an anti-quark) eg pions, kaons
A strong force holds ?
quarks together and also holds protons and neutrons together in the nucleus
Beta decay is caused by ?
The weak force and is evidence of the neutrino
Anti-matter particles are identical to ?
Their corresponding matter particles except charge
Matter + corresponding anti-matter=
Annihilation
Electric field lines point
From positive to negative
A charged particle will accelerate in an electric field because ?
It’s experiences an unbalanced force
Gain in kinetic energy =
Work done by electric field
Like charges
Repel
Opposite charges
Attract
Potential difference (voltage)
Is the number of joules of energy per coulomb of charge
A moving charges particle
Will produce a magnetic field
Magnetic field
Lines point from north to south
Nuclear fission
Big nucleus splitting into smaller parts
Induced/ simulated fission
Usually caused by neutron bombardment
Spontaneous fission
Random event, no external trigger
Nuclear fusion
Smaller parts combining to make a more massive nucleus
The products of a nuclear reaction have
Less mass than the particles did before
The high temperatures required in a fusion reactor lead to
Coolant and containment issues
The photoelectric effect is proof that
Light is a partial
Interference is the proof that
Light is a wave
The work function of a metal is
The minimum energy required to cause photoemission
The threshold
Minimum frequency of incident to cause photoemission
Constructive interference is when?
Two coherent waves meet in phase (ie crest meets crest and trough meets trough) they combine to produce a maximum
Destructive interference is when
Two coherent waves meet exactly out of phase (ie crest meets trough and trough meets crest) the cancel out producing a minimum
Path difference is
The difference in the length of two paths the waves take
0,1,2,3 wave difference
Maxima / constructive interference
1/2, 1^1/2, 2^1/2 wavelength difference
Minima / destructive interference
In terms of diffraction grating D is
The spacing between consecutive lines ie 300 lines per mum means d=1/300 000m
In terms of diffraction grating theta is
The angle between the centre maximum and the maximum you are considering
Absolute refractive index of a medium is
The ratio of the speed of light in a vacuum to the speed of light in the medium
The critical angle of a medium is
The angle of incidence inside the medium which results in a refracted angle of 90° in a vacuum
Total internal reflection occurs when
The angle of incidence inside the medium is greater that the critical angle
Irradiance of radiation is
The power per unit area ie the number of watts per square metre incident on a surface
From a point force
Irradiance follows the inverse square law ie if the distance is doubled (x2) then the irradiance will quarter
Line emission spectra are produced as
Each electron that falls from a high energy level to a lower level will result in specific energy and therefore frequency/wavelength/colour of photon
Absorption spectra occurs when
The atoms absorb specific energies of photons and the electrons move up to the relevant levels.
Coherent waves mean
Constant phase difference (same frequency)
