Physics A-LEVEL__Particles Flashcards
What is a nucleon?
the particles found in the nucleus - protons and neutrons
What is the nucleon number?
number of protons and neutrons
What is the definition of nuclide notation?
shows summary of information about the atomic structure
What is the proton number?
the number of protons in the nucleus
What is the charge of a proton?
+1 (GCSE)
+1.6x10*-19 (A-LEVEL)
What is the mass of a proton?
1.67x10*-27
What is the charge of a neutron?
0
What is the mass of a neutron?
1.67x10*-27
What is the charge of an electron?
-1 (GCSE)
-1.6x10*-19 (A-LEVEL)
What is an isotope?
Isotopes are atoms of the same element but have the same number of protons but different number of neutrons
What will happen to the proton and nucleon number of an isotope?
- the proton number will stay the same <br></br>-the nucleon number will be different
What is the definition of specific charge?
the ratio of the charge of an ion or subatomic particle to its sub-atomic particle: charge-mass ratio
What is the formula for specific charge?
Specific charge = charge/mass
What is the formula of specific charge (detail)?
specific charge = (+1.6x10-19) x no.protons
/(1.67x10-27)x nucleon number
What are the four interactions?
Electromagnetic interaction - causes an attractive and repulsive force between charges
Gravitational interaction - causes attractive forces between masses
Strong nuclear interaction - causes attractive and repulsive forces between quarks (so hadrons)
Weak nuclear interaction - does not cause force however makes particles decay
what type of interaction effects protons and neutrons?
strong nuclear
what type of interaction effects charged particles
electromagnetic
what is the distance between nucleons measured in?
fentometers (fm)
what is 1fm equal to in m?
1x10-15
For strong nuclear force when is it repulsive?
Repulsive at separations of nucleons less than 0.5fm
when is there a strong attraction for the nuclear force?
there is a strong attraction between 0.5fm-3fm
For electromagnetic force when is it always repulsive?
always repulsive from 1fm
what happens during alpha decay?
an alpha particle is released (<b>2 protons + 2 neutrons</b>) from the nucleus as the nucleus is too large for the forces to hold nucleons in place
what effect does alpha decay have on the proton number?
the proton number decreases by two
what effect does alpha decay have on the nucleon number?
nucleon number decreases by 4
what happens during beta-minus decay?
nucleus is unstable and a <b>neutron changes into a proton </b>- a beta particle is <span>released (electron) and an electron anti-neutrino</span>
what is the definition of a photon?
photons are em waves that can only exist in wave packets of energy
what is the equation for energy carried by a photon?
<span>E = hf</span><br></br><ul><li>E = energy (J)</li><li>h = Planck’s constant (Js)</li><li>f = frequency (Hz)</li></ul>
what is another equation for energy carried by photon involving wavelength?
<span>E = hc/wavelength<br></br></span>E = energy (J)<br></br>h = Plancks constant <br></br>c = speed of light (m/s)
what is the value of Plancks constant?
6.63 x10-34
what is the value of speed of light?
3x10*8
what is an electronvolt?
an electronvolt is the amount of energy gained by an electron as it accelerates through a potential difference of 1 volt
how to convert between 1ev to J?
x1.6x10-19
how to convert between J to eV?
divide by 1.6x10-19
what is matter and antimatter?
for every particle there will be its antimatter for example the antimatter of a proton is antiproton
what are the properties of antimatter?
<ul><li>opposite charge</li><li>same mass </li><li>same rest energy</li></ul>
what is the antiparticle of a proton and its charge?
antiproton <br></br>-1
what is the antiparticle of a neutron and its charge?
antineutron<br></br>0
what is the antiparticle of an electron and its charge?
positron<br></br>+1
what is the antiparticle of a neutrino and its charge?
antineutrino<br></br>0
what is the definition of pair production?
when energy is converted into mass you get equal amount of matter and antimatter
what happens during pair production?
a single photon of energy is converted into a particle-antiparticle pair
what happens to the left over energy in pair production?
the leftover energy is converted into kinetic energy (momentum)
what happens during annihilation?
annihilation occurs when a particle and its antiparticle meet and <b>mass is coverted into energy </b>in which the particle and antiparticle are transformed into <b>two photons of energy </b>
why are two photons of energy produced in annihilation?
one photon for rest energy<br></br>one photon for momentum
how is minumum energy calculated?
2 x particle rest energy
what are quarks?
quarks are smaller particles with fractional charge which are contained in protons and neutrons
what does it mean when quarks are fundamental?
fundamental means the quarks are not made of anything smaller
what are the three types of quarks?
d - down<br></br>u - up<br></br>s - strange
what are the three properties might quark will have?
charge <br></br>baryon number <br></br>strangeness
what will the charge, BN and strangeness be for an antiquark?
they will all be the opposite
what is the quark composition of a proton?
uud
what is the quark composition of a neutron?
udd
what are hadrons?
hadrons are a type of particle which are heavy and made from smaller particles
what are the two categories of hadrons?
Baryons - made up of quarks (or 3 antiquarks)
Mesons - made of quarks: one matter and one antimatter
what are examples of baryons?
protons and neutrons
what are examples of mesons?
kaons and pions
