other paper 1 things Flashcards
(34 cards)
if the charge of a particle is negative what will the specific charge be
negative
what are hydrogens two isotopes
deuterium and tritium
Why must the SNF exist
the gravitational gorce is extremely weak therefore there must be a force that counteracts the EM force in order to keep nuclei stable
what is exchange particle for quarks and hadrons
hadrons - pion
quarks - gluon
when will seperation between nucleons be equilibrium
when EM + SNF = 0
how was the existence of the neutrino hypothesized
- total energy released during beta decay is constant however beta particles have continuous range of kinetic energy’s therefore there must be a neutrino that accounts for this
what is the minimum energy of a 1 photon after annihalation
the rest energy of 1 of the particles
what is the mninium energy for a photon to undergo pair production
both of the particles rest energys combined
how is a kaon created and how does it decay
kaon created through the strong force in a quark anti quark pair to conserve strangeness
kaon decays into pion + and pion - through the weak interaction
how does exchange particles mediate forces
exchange particles have momentum therefore the conservation of momentum in there interactions causes changes in momentum in particles
properties of a virtual photon
no charge, no mass, its own antiparticle
why is electron capture a W+ and electron proton collision a W-
- caprure - the proton initiates the interaction therefore its a w+
- collision - the electron initiates the reaction therefore it is a w-w
why is the proton and pion the most stable baryon
there is nothing for it to decay into as its decay would violate baryon number rules same with pion
this is because they are the lightest meson and baryon
why aren’t quarks classed as leptons
they interact with the strong force
what is the specific process of beta decay
nuetron/proton decays into proton/nuetron and a W+/W- boson. W+/W- boson decays into a e+/e- and electron nutrino/antielectron nutrino
to do with quarks explain why exchange particles of beta decay have there charge
in beta- down quak is negatice therefore release a negative w boson when decaying to an up quark
reverse for beta plus
why is the stopping potential negative
it needs to oppose the negatively charged electrons
why wont all photoelectrons be emitted with max kinetic energy
they originate from different depths
imperfections in the metal
photon may not be absorbed fully
what is the threshold wavelength
the longest wavelength of light that would cause the photoelectric effect
what is the stopping potential
when the energy transferred by the battery is = to the maximum kinetic energy per electron therefore stopping all photoelectric emission
what is the formula for intensity of light
power per unit area x number of photons
Resistivity
the extent to which a material opposes an electrical current
what are the problems with a thermistor
- current causes increased heating which causes low resistance therefore more current therefore more heating (temperature spiral)
what is the phase difference
the relative difference in position or displacement between a particle or a wave
