Sec 1 - Particles
Atomic Stucture: Cover Me
Inside every A..... theres a n........ containing Ps & Ns Atom Nucleus
what are Ps & Ns both known as , & orbiting this core = the Es Nucleons
For the following state the Relative Charge & Relative Mass :
Proton RC= +1 , RM = 1
Neutron RC= 0 , RM=1
Electron RC= -1 , RM = 0.0005 (5 x 10 to the power of Minus 4)
Proton number = sometimes called Atomic Number, whats its Symbol Z ( z = no. of Ps in the nucleus)
Which subatomic particle defines the Element Proton Number (no 2 elements have the same number of Ps)
whats the deal with a Neutral Atom & subatomic particles P=E
what does the elements reaction & chemical behaviour depend on no. of Es ( so the P. number tells u a lot about an As chemical properties)
whats the Nucleon number the total number of total no. of Ps & Ns (also known as Mass Number)
whats the symbol for the Nucleon number A (since each P. or N. = relative mass = approx 1 & the E. = weighs basically nothing, = the number of Nucleons = same as the Atoms relative mass) (the Nuclide notation of an element summarises info about its atomic structure , basically the Element with the Mass no. on top & the Atomic no. at bottom)
whats the deal with Isotopes different forms of the same element, they = same P. no. but different Nucleon no. (same Atomic no. but different Mass no.) ( As with same no. Ps but different no. of Ns = Isotopes)
which subatomic particle can u change & it wont affect the As chemical Properties + what does it affect No. of Ns + The Stability of the nucleus (unstable nuclei may be radioactive & decay over time into different nuclei that = more stable)
Radioactive I......... can = used = find out how Old stuff is isotopes
what do all living this contain the same percentage of radioactive carbon-14 (taken in from the atmosphere)
whats the deal with after they die the amount of C-14 in em decreases over time as it decays to stable elements
Scientists can calc. the approximate a... of ar....... finds made from dead or.... m....... (eg wood,bone) by using I......... data (amount of each I...... present) to find the % of Radioactive Carbon-14 that=left in the o....... age archaeological organic matter Isotopic isotope object
Define Specific Charge of a Particle + whats the Units = the ratio of its charge to its mass + Coulombs per Kilogram , C kg to the -1
so whats the Formula for Specific Charge Charge / Mass
Stable & Unstable Nuclei:
keeping the Nucelus stable requires a lot of effort , what binds Nucelons together The Strong Nuclear Force (may also = called = Strong interaction)
whats the deal with forces & nucleons in a nucleus there = several different forces acting on the nucleons
theres 2 u already know, E........ forces & g............ forces Electrostatic Gravitational
where do the Electrostatic forces come from electrostatic forces = from the Ps' electric charges
what are the gravitational forces due to the masses of the Particles
if u done the calc.(dont need to ever) =the repulsion from Electrostatic forces = much much bigger than Gravitatioanl force of attraction, if theses = only 2 forces acting in the Nucleus, = the Nucleons wud fly apart, so there must = another attractive force that holds the Nucleus together - = the Strong Nuclear Force
what must there be present to hold the Nucleus together an Attractive force that = stronger than the electrostatic force
what have experiments shown about the Strong Nuclear Force & its range that it = a very short range
whats the deal with the distance up till it can hold nucleons together when theyre seperated it can only hold Nucleons together when theyre seperated -- Up to a Few Femtometers ( 1 fm = 1 x 10 to -15m ) - the size of a nucleus (The strength of the SNF = quickly falls beyond this distance (graph!!!) )
what have exp. also shown about the SNF & the Nucleons the SNF works equally between all nucleons , so = SIZE OF FORCE = same whether its a P-P , P-N or N-N
whats the deal with the SNF at Very Small Seperations SNF must = repulsive or it wud crush the nucleus to a point
what does the size of the SNF vary with varies with Nucleon seperation (SNF can = plotted on a graph= show how it changes with the Distance of Seperation between Nucleons, if Electrostatic F. = also plotted = u can see relationship between these 2 forces )
- The SNF = very r...... for very small seperations of Nucleons repulsive
- when does the SNF become attractive - As Nucleon seperation ^ past about 0.5 fm , = the SNF becomes attractive
^^ whats the deal with what happens afer about 3 fm it reaches a max, attractive value & then falls rapidly towards 0 afer about 3 fm
( the Electrostatic Repulsive force extends over a much larger range , indefinitely)
Em....... happens in very big N.... Emmission Nuclei
whats the deal with when Alpha Emission only happens Alpha emmission only happens in very big nuclei, like Uranium & radium
whats the deal with the nuclei of these atoms The nuclei of these atoms = just too massive for the SNF = keep them stable
what happens when an Alpha Particle is emmitted the P. number (Atomic Number but u dont call it that anymore) decreases by 2, & the Nucleon no. decreases by 4 (the Mass No.)
Alpha Particles have a very s.... range , only few cm in a... short air
what 2 ways can u see the short distance that Alpha Particles (APs) travel by observing tracks left by the APs in a Cloud Chamber, also a Geiger counter (a device=measures the amount of ionising radiation) , u bring it up close to the Alpha Source, then move it away slowly & observe how the count rate drops
In what sorta Nuclei does Beta-Minus (or just Beta=usually called) decay occur in a Neutron-Rich Nuclei
what is Beta decay the Emission of = of an E. from the nucleus along with a Antineutrino
Beta Decay happens in I...... that = un........ due to being 'Neutron-Rich' Isotopes Unstable ( Neutron-Rich = ie = they have too many more Ns than Ps in the Nucleus )
what happens when the Nucleus Ejects a Beta Particle one of the Ns in the nucleus = changed into a P.
what happens to the P. No. & the Nucleon no. when a Beta decay happens P. no. = ^ by 1 , Nucleon no. stays the same
in Beta decay u get a tiny n...... particle called a antineutrino released, this = carries away some e..... & m......... neutral energy momentum
Observations of what exactly led to the hypothesis of the existence of the Neutrino Observations of Beta Decay
- What did Scientists originally think happend during Beta decay that the only Particle emmitted from the Nucleus during beta decay = an E,
- tho what did Observations show about the energy of the particles 2 that the En of particles after the Beta decy = less than it was before , which didnt = fit with principle = conservation of En
- (1930) what did Wolfgang Pauli suggest 2 that another particle was being emmitted too , & it carried away the missing En
- whats the deal with this suggested particle 2 Had to = Neutral (or charge woudn't = conserved in Beta Decay) + Had to = have 0 or almost 0 mass (as it'd never been Detected)
- Other discoveries led to Pauli's theory = accepted & the Particle = named = Neutrino (we know now it as the AntiNeutrino)
- The Neutrino = eventually observed 25 Years later = providing evidence for Paulis hypothesis
Particles & Antiparticles:
VL = just 1 typa EM radiaton, the EM spectrum =a continuous spectrum of all the possible F.......... of EM radiation Frequencies (photons are packets of EM radiation)
whats the equation that links Freq. & WL (not GCSE one btw) Freq. = C / WL C = 3 x 10 to the 8 , speed of light in a vaccum (sometimes = the speed of light in vacuo)
what does EM radiation exist as photons of En
The En of a Photon depends on the F. of the radiation, E = hf = hc / WL (h=Planck constant)
Every particle has a .............. AntiParticle
Each Particle has a matching antiparticle , with the same what 2 things But w/ opp. what (amongst other things) same mass & rest En opp. charge
whats the same for both the Particle & the AntiParticle 2 Mass & Rest En (anti- & neutrinos = incredibly tiny = u can assume they = 0 mass & rest En
what can u create from En + what are these 2 things you can create Matter & Antimatter from Energy + Matter = basically particles with mass & Energy = Photons
whats the Equivalence of En & Mass That En can turn into Mass & Mass can turn into En
The rest En of a particle = just the 'En equivalent' of the Particles Mass, meausred in MeV, u cant work it out = using formula = E=mc squared
what do u get equal amounts of when En = converted into Mass Matter & AntiMatter
FIre 2 Ps at each other at high speed & youll = end up with a lot En at point of impact, this En might=converted into more particles
^^ so if an extra proton is formed then what will always go with it + whats this called an AntiProton + called = Pair Production
what is each Particle - AntiParticle pair produced from a Single Photon (image)
E...... that gets converted into matter & antimatter = in the form of a p..... Energy photon
when does Pair Production only happen if one photon has enuf En = produce that much mass (or it can be 2 high en. gamma ray photons colliding & forming an electron-positron pair)
which type of Photon has enough En for the above Gamma Ray Photon
where does it also tend to happen near + why it also tends to happen near a nucleus, which = helps conserve Momentum
whats usually produced rather than what + why usually = E.- Positron pairs = produced rather than any other pair + cos they have a relatively low mass
what is the min. En for a Photon undergo Pair Production the same as (the other equation i wrote on the whiteboard?????) as the TOTAL Rest En of the particles produced (if 2 produced then its 2Eo) ( the Particle & Anti-Particle = rest En of Eo, so - Emin = HFmin = 2Eo )
Whats the deal with Annihilation ( opp. of Pair Production) When a Particle meets an Anti-Particle = the result = Annihilation
what gets converted back into En when the 2 collide together All the mass of the Particle & AntiParticle get converterd back to En
^^ why dont u get APs in ordinary matter APs can usually only exist for a fraction of a sec before this happens, so u dont get em in ordinary matter)
An a.......... is between a Prt.-A.Prt pair, which both have a Rest En of Eo annihilation
Both Photons need to have a min En, Emin, which when added together equals at least 2Eo for En to be conserved in this interaction, So 2Emin = 2Eo
^^ & Emin = HFmin = Eo
since its Emin, any extra En is turned into Ek
Forces & Exchange Particles:
What are forces caused by Particle exchange (u cant have instantaneous action at a distance so when 2 particles interact, something must happen to let one particle know the other ones there, thats the idea behind exchange particles, has to be some sort of info exchange to let them know for eg 2 Es to know to repel each other
imagine 2 people are on 2 seperate boats close together, whats the deal with what happens when a ball is thrown/caught + why Repulsion occurs, the ppl get pushed apart + cos the ball carries momentum
^^ Attraction o..... , whats the deal with when a boomerang is thrown/caught around (theyre facing away and chuck it round till it curves round fully...) Attraction occurs, The ppl get pushed together
what are these exchange particles called (particles that cause forces) Gauge Bosons ( The repulsion between 2 Ps is caused by the Exchange of Virtual Photons, which = the Gauge Bosons of the EM force )
whats the deal wiith Gauge Bosons theyre Virtual Particles - they only exist for a very short time (they basically carry the force involved (4 fundamental forces))
what do exchange particles do in an interaction 3 transfer momentum, transfer energy, transfer force
what are all forces in Nature caused by 4 four fundamental forces
Name the 4 four fundamental forces EM, SNF, Weak Nuclear Force, & gravity
what does each Fundamental force has its own of Gauge Boson
For the following forces name its Gauge Boson + the Particles it affects : ( gravity isnt bothered with cos its incredibly feeble compared with other types of interaction, Gravity only really matters when uve got big mass eg stars, planets
EM Virtual Photon (same symbol as normal photon) + Charged particles only
Weak NF W to the + , W to the - , all types
SNF 2 Pions Pi to the + , to the -, & to the 0 + in the SNF, pions are described as being exchanged between Nucleons might also be described as Gluons being exchanged between Quarks
whats the deal with the Larger the Mass of the Gauge Boson the Shorter the range of the force
The .. Bosons have a m.... of about ....... times than that of a Proton, which gives the w..... force a very short r..... W mass 100 weak range ( creating a Virtual W particle uses so much En that it can only exist for a very short time & it cant travel far )
On the other hand, whats the deal with the Photon 2 has 0 mass, which gives you a force wtih Infintie Range
( Diagrams used = show Particle Interactions, squiggly lines = the Gauge Bosons, Other Particles = represented by Straight lines ) (diagram on ur board m8) the 2 particles come together & then a photon travels from one to the other as the gauge boson for eg , & this causes them to like seperate away because the gauge boson caused that interaction
EM repulsion: whats the deal with EM repulsion when 2 particles with equal charges get close to each other, they repel
Electron Capture: what are Es & Ps attracted by the EM interaction between them
^^ but if a P. c....... an E., the w.... interaction can make this interaction happen ( makes it capture the E. i think) captures weak
whats the equation for the above interaction P + E. ---> N + Ve ( Ve = neutrino )
+ Electron - Proton collisions : where an E. collides with a P. , the equation for this collision is the same as E. capture, but whats the difference in the diagram, instead of a W+ boson going from the P to the E. , theres a W- boson going from the E. to the P.
Beta+ Decay : whats the equation P -----> N + E to the + ( positron basically ) + Ve
Beta- Decay : whats the equation N ----> P + E. + Anti-Ve ( antineutrino, basically the Ve thing like above but with a line on top of it, so ill just type anti-Ve )
(whats the difference between the 2 ) if leptons involved = weak interaction B+ = a neutrino & starts with a P. , B- = antineutrino & starts with a N. ( its different both so the Lepton number is convserved )
Classification of Particles:
Hadrons are particles , do they feel the SNF or not yes they do feel the SNF
whats the Nucleus of an Atom made up of Ps & NS
Since the Ps are p........ charged they need a strong f..... to hold them together , this = called the SNF or Strong Interaction positively force
what can not all particles feel the SNF ( the ones that can = called Hadrons )
Hadrons arent f............. particles , what are they made up of Fundamental , smaller particles called quarks
how many types of Hadrons are there . 2
whats the names of the 2 types of Hadrons Baryons ( & AntiBaryons) + Mesons ( theyre classified according to the no. of Quarks that make them up, but dw but that for now.....)
which type of Hadron are Ps & Ns Baryons
whats the deal with the Proton as a Baryon 2 its the only Baryon thats stable , all other Baryons (except Ps) = Unstable
what does this mean for all the other Baryons that are unstable ( unlike the P. ) then that they decay to become other particles
what does the particles a baryon ends up as depend on + but what does it always include on what it started with ( so i think thats basically the particle that it started with ) + Always includes a Proton
Protons = the only s..... b..... , they dont d...... as far as we know stable Baryons decay
what type of Baryons are AntiPs & AntiNs AntiBaryons
tho AntiParticles are a............ when they meet the corresponding particle , which means u dont find any AntiBaryons in o....... matter annihilated ordinary
what is the no. of Baryons in an interaction called the Baryon number ( it says it also includes unusual baryons as well ( like ones u dont get in normal matter, like how it mentioned Sigma before as Other Baryon i dont needa know
whats the Baryon number of the P. & N. B = +1
whats the Baryon number of AntiBaryons B = -1
wb the Baryon no. of Other Particles ( ie things that arent Baryons ) theyre given a Baryon number - B = 0
Baryon no. is a q......... number that must be c....... in any interaction , this means it can only take a certain set of values quantum conserved ( so u dont get like some random decimal no. eg 1.98945 or 2.684234 )
whats the deal with the Baryon number when an interaction happens ( the total B. no. in any particle interaction never changes ) the Baryon number on either side of the Interaction has to be the same ( u can use this = predict when an interaction will happen , if the numbers dont match , it cant happen )
Ns are b..... that decay into Ps baryons ( beta decay = N. changing into a P. , this happens when theyre = many more Ns than Ps in a nucleus , or when a Neutron is by itself outside of a nucleus )
which Interaction is Beta Decay caused by Weak Interaction (ig cos quark type changed)
N. decays = forms a Proton , an Electron & an Antineutrino , n --> P + E + AntiNeutrino
Electrons & AntiNeutrinos arent Baryons , theyre Leptons, so they = Baryon no. - B = 0, Ns & Ps = Baryons & so = B. no. = B = 1 , this means the Baryons no.s on both sides are equal, so the interaction can happen
The other type of Hadron is a M..... , which 2 types of M..... do u need to know Mesons Mesons + Pions Kaons ( & it says theres ' Other Mesons ' as well )
whats the deal with all Mesons 2 ( ie whats their stability like & Baryon no. ) All Mesons are Unstable + & have a Baryon Number B=0
whats the deal with Pions ( Pi - Mesons ) 2 they are the lightest Mesons , u get 3 different version with different electric charges - Pi to the + , to the -, & to the 0
when do u get loads of Pions in high En particle collisions ( like those studied at the CERN particle accelerator )
whats the deal with Kaons ( K - Mesons ) in reference to Pions 2 + what sorts do u get are Heavier & more Unstable than Pions , u get different ones like K to the + & K to the 0
whats the deal with their lifetime + what do they decay into Kaons = very short lifetime + decay into Pions
Kaons app have a unexpectdely long lifetime cos they have a S......... Quark Strange
What were discovered in C...... r..... , & so C..... r..... S....... are a source of both particles, u can observe the tracks of these particles with a c....... c......... Pions & Kayons Cosmic Rays Cosmic Ray Showers Cloud Chamber
...... in....... with ..... via the Strong Force Mesons Interact Baryons ( Pions interactions swap Ps with Ns & Ns with Ps, but leave the overall Baryon no. unchanged )
whats the deal with Letpons ( eg Es & Neutrinos ) 2 + wb exchange particles - fundamental or not? they dont feel the SNF, Theyre Fundamental Particles, (exchange particles also come under theh branch of 'fundamental particles')
they only really i...... with other p...... via the W..... interaction , ( along with a bit of gravitational force & the EM force as well if theyre charged ) interact particles weak
Es are s..... & very familiar , but there = also other L....., such as the M.... ( symbol), that are just like h...... Es stable Leptons Muons heavy
whats the deal with Muons 2 they = Unstable , & decay eventually into Ordinary Es
The E. & Muon L..... each come with their own n...... , Ve & V ( small Muon symbol ) Lepton neutrino
whats the deal with Neutrinos 2 + what sort of interaction do they ONLY take part in they have 0 or almost 0 mass & 0 electric charge ( so they dont do much) Weak Interactions
Like the Baryon no. , the Lepton no. is just the no. of Leptons, Each Letpon = Lepton no. = +1, But u have to count the TYPE of Lepton seperately, so the E & Muon type of Lepton have to be counted seperately , u get different Lepton numbers, Le & L ( small Muon symbol ) look on Board for all the no. , charge stuff
Quarks:
Quarks are f.......... particles, what are Quarks the building blocks for (the fundamentals for) fundamental, Quarks = the building blocks for Hadrons ( baryons & mesons )
what are the AntiParticles of Hadrons made from AntiQuarks
how many types of Quarks dyu need to make Ps & Ns + what are they only 2 types, the up Quark (u) & the down Quark (d)
An extra one called the S...... quark (s) lets u make m.... particles with a property called s............. Strange more Strangeness
Strangeness is only c........... some of the time, Strangeness, like B....... no., is a q..........number - it can only take a certain set of values Conserved Baryon Quantum
Strange Particles eg kaons are created via what force + decay via what other force Strange Particles = Created via the Strong Interaction + Decay via the Weak Interaction
tho in which of those 2 interactions is Strangeness conserved & which one is it not conserved in Strangeness = conserved in the Strong Interaction , But not in the Weak interaction
This means Strange P....... are Always produced in p....... ( eg K to the +, & to the -), one has a strangeness of +1, & the other = Strangeness of -1, so overall Strangeness of 0 = Conserved Particles Pairs
How many Quarks are Baryons made from 3 Quarks
from what did Evidence of Quarks come from ( Learn the charges for each u d s for both anti & normal, also on the board is the Combination of Quarks that u need to know for both Ps, Ns & their Antis, yes u guessed it there Anti-make up of Quarks is the opposite charge ) Evidence for Quarks came from hitting Ps with high- En Es
^^ what did the way the Es scattered show that there were 3 concentrations of charge (quarks) Inside the P.
M..... consist of a Q..... & an A...... Mesons Quark AntiQuark
whats the deal with what Pions are made from Pions = made from combinations of Up, down, Anti-up & Anti-down Quarks
Kaons have s........... so u need to put in s Quarks as well , whats the Strangeness value of an s Quark Strangeness -1
For the following Mesons, tell me their Quark & Anti-Quark composition + also their Strangeness value :
K to the 0 (kaon) d & anti-S S = +1
K to the + u & anti-S S = +1
Pi to the + (pion) u & anti-d S=0
Pi to the 0 2 u & anti-U , d & anti-down S=0
Pi to the - d & anti-U S=0
Anti-K to the 0 s & anti-d S = -1
K to the - s & anti-U S = -1
The Pi to the - meson is just the AntiParticle of the Pi to the + Meson , the K to the - Meson is just the AntiParticle to the K to the + Meson
And the Antiparticle of the Pi to the 0 meson is itself (N-udd, P-uud)
The w...... I...... is smthn that Changes Q...... t....... Weak interaction Quark type
In Beta Minus decay , whats changed into what else a N. = changed into a P.
^^ how do u say that in terms of Quarks udd changes into uud ( if u look at the charges for it .... it works, it goes from a Neutron when the udd Quarks added to 0 , to a P. where they add to 1, which = overall P. charge!
Some U........ I......... like Carbon-11 decay by Beta Emission, in this case what happens a P. changes to a N., so u get a u Quark changinig to a d quark ( & so that changes the Quark charge to = the charge of a N. )
How many properties are conserved in Particle Interactions .4
C.... is always conserved, in Any particle interaction, the t..... c.... after the interaction must equal the total charge before the Interaction Charge Total Charge
B..... no. is always conserved, Just like with charge, in Any particle interaction, the Baryon no. after the int. must = the baryon no. before the int.
Conservation of Lepton no. is a bit more complicated, ! The d........ types of Leptons have to be conserved S......... different Seperately
Theres no such thing as a f.... Quark free
if u blasted a P. with enuf En cud u seperate the Quark? Nope, whatd happen to the En The En of it wud just het changed into more Quarks & Anti-Quarks
^^ its P... P......... again & u just make M..... Pair Production Mesons ( Mesons cos theyre only made up of a Quark & Anti-Quark )
Atomic Stucture: Cover Me
Inside every A..... theres a n........ containing Ps & Ns Atom Nucleus
what are Ps & Ns both known as , & orbiting this core = the Es Nucleons
For the following state the Relative Charge & Relative Mass :
Proton RC= +1 , RM = 1
Neutron RC= 0 , RM=1
Electron RC= -1 , RM = 0.0005 (5 x 10 to the power of Minus 4)
Proton number = sometimes called Atomic Number, whats its Symbol Z ( z = no. of Ps in the nucleus)
Which subatomic particle defines the Element Proton Number (no 2 elements have the same number of Ps)
whats the deal with a Neutral Atom & subatomic particles P=E
what does the elements reaction & chemical behaviour depend on no. of Es ( so the P. number tells u a lot about an As chemical properties)
whats the Nucleon number the total number of total no. of Ps & Ns (also known as Mass Number)
whats the symbol for the Nucleon number A (since each P. or N. = relative mass = approx 1 & the E. = weighs basically nothing, = the number of Nucleons = same as the Atoms relative mass) (the Nuclide notation of an element summarises info about its atomic structure , basically the Element with the Mass no. on top & the Atomic no. at bottom)
whats the deal with Isotopes different forms of the same element, they = same P. no. but different Nucleon no. (same Atomic no. but different Mass no.) ( As with same no. Ps but different no. of Ns = Isotopes)
which subatomic particle can u change & it wont affect the As chemical Properties + what does it affect No. of Ns + The Stability of the nucleus (unstable nuclei may be radioactive & decay over time into different nuclei that = more stable)
Radioactive I......... can = used = find out how Old stuff is isotopes
what do all living this contain the same percentage of radioactive carbon-14 (taken in from the atmosphere)
whats the deal with after they die the amount of C-14 in em decreases over time as it decays to stable elements
Scientists can calc. the approximate a... of ar....... finds made from dead or.... m....... (eg wood,bone) by using I......... data (amount of each I...... present) to find the % of Radioactive Carbon-14 that=left in the o....... age archaeological organic matter Isotopic isotope object
Define Specific Charge of a Particle + whats the Units = the ratio of its charge to its mass + Coulombs per Kilogram , C kg to the -1
so whats the Formula for Specific Charge Charge / Mass
Stable & Unstable Nuclei:
keeping the Nucelus stable requires a lot of effort , what binds Nucelons together The Strong Nuclear Force (may also = called = Strong interaction)
whats the deal with forces & nucleons in a nucleus there = several different forces acting on the nucleons
theres 2 u already know, E........ forces & g............ forces Electrostatic Gravitational
where do the Electrostatic forces come from electrostatic forces = from the Ps' electric charges
what are the gravitational forces due to the masses of the Particles
if u done the calc.(dont need to ever) =the repulsion from Electrostatic forces = much much bigger than Gravitatioanl force of attraction, if theses = only 2 forces acting in the Nucleus, = the Nucleons wud fly apart, so there must = another attractive force that holds the Nucleus together - = the Strong Nuclear Force
what must there be present to hold the Nucleus together an Attractive force that = stronger than the electrostatic force
what have experiments shown about the Strong Nuclear Force & its range that it = a very short range
whats the deal with the distance up till it can hold nucleons together when theyre seperated it can only hold Nucleons together when theyre seperated -- Up to a Few Femtometers ( 1 fm = 1 x 10 to -15m ) - the size of a nucleus (The strength of the SNF = quickly falls beyond this distance (graph!!!) )
what have exp. also shown about the SNF & the Nucleons the SNF works equally between all nucleons , so = SIZE OF FORCE = same whether its a P-P , P-N or N-N
whats the deal with the SNF at Very Small Seperations SNF must = repulsive or it wud crush the nucleus to a point
what does the size of the SNF vary with varies with Nucleon seperation (SNF can = plotted on a graph= show how it changes with the Distance of Seperation between Nucleons, if Electrostatic F. = also plotted = u can see relationship between these 2 forces )
- The SNF = very r...... for very small seperations of Nucleons repulsive
- when does the SNF become attractive - As Nucleon seperation ^ past about 0.5 fm , = the SNF becomes attractive
^^ whats the deal with what happens afer about 3 fm it reaches a max, attractive value & then falls rapidly towards 0 afer about 3 fm
( the Electrostatic Repulsive force extends over a much larger range , indefinitely)
Em....... happens in very big N.... Emmission Nuclei
whats the deal with when Alpha Emission only happens Alpha emmission only happens in very big nuclei, like Uranium & radium
whats the deal with the nuclei of these atoms The nuclei of these atoms = just too massive for the SNF = keep them stable
what happens when an Alpha Particle is emmitted the P. number (Atomic Number but u dont call it that anymore) decreases by 2, & the Nucleon no. decreases by 4 (the Mass No.)
Alpha Particles have a very s.... range , only few cm in a... short air
what 2 ways can u see the short distance that Alpha Particles (APs) travel by observing tracks left by the APs in a Cloud Chamber, also a Geiger counter (a device=measures the amount of ionising radiation) , u bring it up close to the Alpha Source, then move it away slowly & observe how the count rate drops
In what sorta Nuclei does Beta-Minus (or just Beta=usually called) decay occur in a Neutron-Rich Nuclei
what is Beta decay the Emission of = of an E. from the nucleus along with a Antineutrino
Beta Decay happens in I...... that = un........ due to being 'Neutron-Rich' Isotopes Unstable ( Neutron-Rich = ie = they have too many more Ns than Ps in the Nucleus )
what happens when the Nucleus Ejects a Beta Particle one of the Ns in the nucleus = changed into a P.
what happens to the P. No. & the Nucleon no. when a Beta decay happens P. no. = ^ by 1 , Nucleon no. stays the same
in Beta decay u get a tiny n...... particle called a antineutrino released, this = carries away some e..... & m......... neutral energy momentum
Observations of what exactly led to the hypothesis of the existence of the Neutrino Observations of Beta Decay
- What did Scientists originally think happend during Beta decay that the only Particle emmitted from the Nucleus during beta decay = an E,
- tho what did Observations show about the energy of the particles 2 that the En of particles after the Beta decy = less than it was before , which didnt = fit with principle = conservation of En
- (1930) what did Wolfgang Pauli suggest 2 that another particle was being emmitted too , & it carried away the missing En
- whats the deal with this suggested particle 2 Had to = Neutral (or charge woudn't = conserved in Beta Decay) + Had to = have 0 or almost 0 mass (as it'd never been Detected)
- Other discoveries led to Pauli's theory = accepted & the Particle = named = Neutrino (we know now it as the AntiNeutrino)
- The Neutrino = eventually observed 25 Years later = providing evidence for Paulis hypothesis
Particles & Antiparticles:
VL = just 1 typa EM radiaton, the EM spectrum =a continuous spectrum of all the possible F.......... of EM radiation Frequencies (photons are packets of EM radiation)
whats the equation that links Freq. & WL (not GCSE one btw) Freq. = C / WL C = 3 x 10 to the 8 , speed of light in a vaccum (sometimes = the speed of light in vacuo)
what does EM radiation exist as photons of En
The En of a Photon depends on the F. of the radiation, E = hf = hc / WL (h=Planck constant)
Every particle has a .............. AntiParticle
Each Particle has a matching antiparticle , with the same what 2 things But w/ opp. what (amongst other things) same mass & rest En opp. charge
whats the same for both the Particle & the AntiParticle 2 Mass & Rest En (anti- & neutrinos = incredibly tiny = u can assume they = 0 mass & rest En
what can u create from En + what are these 2 things you can create Matter & Antimatter from Energy + Matter = basically particles with mass & Energy = Photons
whats the Equivalence of En & Mass That En can turn into Mass & Mass can turn into En
The rest En of a particle = just the 'En equivalent' of the Particles Mass, meausred in MeV, u cant work it out = using formula = E=mc squared
what do u get equal amounts of when En = converted into Mass Matter & AntiMatter
FIre 2 Ps at each other at high speed & youll = end up with a lot En at point of impact, this En might=converted into more particles
^^ so if an extra proton is formed then what will always go with it + whats this called an AntiProton + called = Pair Production
what is each Particle - AntiParticle pair produced from a Single Photon (image)
E...... that gets converted into matter & antimatter = in the form of a p..... Energy photon
when does Pair Production only happen if one photon has enuf En = produce that much mass (or it can be 2 high en. gamma ray photons colliding & forming an electron-positron pair)
which type of Photon has enough En for the above Gamma Ray Photon
where does it also tend to happen near + why it also tends to happen near a nucleus, which = helps conserve Momentum
whats usually produced rather than what + why usually = E.- Positron pairs = produced rather than any other pair + cos they have a relatively low mass
what is the min. En for a Photon undergo Pair Production the same as (the other equation i wrote on the whiteboard?????) as the TOTAL Rest En of the particles produced (if 2 produced then its 2Eo) ( the Particle & Anti-Particle = rest En of Eo, so - Emin = HFmin = 2Eo )
Whats the deal with Annihilation ( opp. of Pair Production) When a Particle meets an Anti-Particle = the result = Annihilation
what gets converted back into En when the 2 collide together All the mass of the Particle & AntiParticle get converterd back to En
^^ why dont u get APs in ordinary matter APs can usually only exist for a fraction of a sec before this happens, so u dont get em in ordinary matter)
An a.......... is between a Prt.-A.Prt pair, which both have a Rest En of Eo annihilation
Both Photons need to have a min En, Emin, which when added together equals at least 2Eo for En to be conserved in this interaction, So 2Emin = 2Eo
^^ & Emin = HFmin = Eo
since its Emin, any extra En is turned into Ek
Forces & Exchange Particles:
What are forces caused by Particle exchange (u cant have instantaneous action at a distance so when 2 particles interact, something must happen to let one particle know the other ones there, thats the idea behind exchange particles, has to be some sort of info exchange to let them know for eg 2 Es to know to repel each other
imagine 2 people are on 2 seperate boats close together, whats the deal with what happens when a ball is thrown/caught + why Repulsion occurs, the ppl get pushed apart + cos the ball carries momentum
^^ Attraction o..... , whats the deal with when a boomerang is thrown/caught around (theyre facing away and chuck it round till it curves round fully...) Attraction occurs, The ppl get pushed together
what are these exchange particles called (particles that cause forces) Gauge Bosons ( The repulsion between 2 Ps is caused by the Exchange of Virtual Photons, which = the Gauge Bosons of the EM force )
whats the deal wiith Gauge Bosons theyre Virtual Particles - they only exist for a very short time (they basically carry the force involved (4 fundamental forces))
what do exchange particles do in an interaction 3 transfer momentum, transfer energy, transfer force
what are all forces in Nature caused by 4 four fundamental forces
Name the 4 four fundamental forces EM, SNF, Weak Nuclear Force, & gravity
what does each Fundamental force has its own of Gauge Boson
For the following forces name its Gauge Boson + the Particles it affects : ( gravity isnt bothered with cos its incredibly feeble compared with other types of interaction, Gravity only really matters when uve got big mass eg stars, planets
EM Virtual Photon (same symbol as normal photon) + Charged particles only
Weak NF W to the + , W to the - , all types
SNF 2 Pions Pi to the + , to the -, & to the 0 + in the SNF, pions are described as being exchanged between Nucleons might also be described as Gluons being exchanged between Quarks
whats the deal with the Larger the Mass of the Gauge Boson the Shorter the range of the force
The .. Bosons have a m.... of about ....... times than that of a Proton, which gives the w..... force a very short r..... W mass 100 weak range ( creating a Virtual W particle uses so much En that it can only exist for a very short time & it cant travel far )
On the other hand, whats the deal with the Photon 2 has 0 mass, which gives you a force wtih Infintie Range
( Diagrams used = show Particle Interactions, squiggly lines = the Gauge Bosons, Other Particles = represented by Straight lines ) (diagram on ur board m8) the 2 particles come together & then a photon travels from one to the other as the gauge boson for eg , & this causes them to like seperate away because the gauge boson caused that interaction
EM repulsion: whats the deal with EM repulsion when 2 particles with equal charges get close to each other, they repel
Electron Capture: what are Es & Ps attracted by the EM interaction between them
^^ but if a P. c....... an E., the w.... interaction can make this interaction happen ( makes it capture the E. i think) captures weak
whats the equation for the above interaction P + E. ---> N + Ve ( Ve = neutrino )
+ Electron - Proton collisions : where an E. collides with a P. , the equation for this collision is the same as E. capture, but whats the difference in the diagram, instead of a W+ boson going from the P to the E. , theres a W- boson going from the E. to the P.
Beta+ Decay : whats the equation P -----> N + E to the + ( positron basically ) + Ve
Beta- Decay : whats the equation N ----> P + E. + Anti-Ve ( antineutrino, basically the Ve thing like above but with a line on top of it, so ill just type anti-Ve )
(whats the difference between the 2 ) if leptons involved = weak interaction B+ = a neutrino & starts with a P. , B- = antineutrino & starts with a N. ( its different both so the Lepton number is convserved )
Classification of Particles:
Hadrons are particles , do they feel the SNF or not yes they do feel the SNF
whats the Nucleus of an Atom made up of Ps & NS
Since the Ps are p........ charged they need a strong f..... to hold them together , this = called the SNF or Strong Interaction positively force
what can not all particles feel the SNF ( the ones that can = called Hadrons )
Hadrons arent f............. particles , what are they made up of Fundamental , smaller particles called quarks
how many types of Hadrons are there . 2
whats the names of the 2 types of Hadrons Baryons ( & AntiBaryons) + Mesons ( theyre classified according to the no. of Quarks that make them up, but dw but that for now.....)
which type of Hadron are Ps & Ns Baryons
whats the deal with the Proton as a Baryon 2 its the only Baryon thats stable , all other Baryons (except Ps) = Unstable
what does this mean for all the other Baryons that are unstable ( unlike the P. ) then that they decay to become other particles
what does the particles a baryon ends up as depend on + but what does it always include on what it started with ( so i think thats basically the particle that it started with ) + Always includes a Proton
Protons = the only s..... b..... , they dont d...... as far as we know stable Baryons decay
what type of Baryons are AntiPs & AntiNs AntiBaryons
tho AntiParticles are a............ when they meet the corresponding particle , which means u dont find any AntiBaryons in o....... matter annihilated ordinary
what is the no. of Baryons in an interaction called the Baryon number ( it says it also includes unusual baryons as well ( like ones u dont get in normal matter, like how it mentioned Sigma before as Other Baryon i dont needa know
whats the Baryon number of the P. & N. B = +1
whats the Baryon number of AntiBaryons B = -1
wb the Baryon no. of Other Particles ( ie things that arent Baryons ) theyre given a Baryon number - B = 0
Baryon no. is a q......... number that must be c....... in any interaction , this means it can only take a certain set of values quantum conserved ( so u dont get like some random decimal no. eg 1.98945 or 2.684234 )
whats the deal with the Baryon number when an interaction happens ( the total B. no. in any particle interaction never changes ) the Baryon number on either side of the Interaction has to be the same ( u can use this = predict when an interaction will happen , if the numbers dont match , it cant happen )
Ns are b..... that decay into Ps baryons ( beta decay = N. changing into a P. , this happens when theyre = many more Ns than Ps in a nucleus , or when a Neutron is by itself outside of a nucleus )
which Interaction is Beta Decay caused by Weak Interaction (ig cos quark type changed)
N. decays = forms a Proton , an Electron & an Antineutrino , n --> P + E + AntiNeutrino
Electrons & AntiNeutrinos arent Baryons , theyre Leptons, so they = Baryon no. - B = 0, Ns & Ps = Baryons & so = B. no. = B = 1 , this means the Baryons no.s on both sides are equal, so the interaction can happen
The other type of Hadron is a M..... , which 2 types of M..... do u need to know Mesons Mesons + Pions Kaons ( & it says theres ' Other Mesons ' as well )
whats the deal with all Mesons 2 ( ie whats their stability like & Baryon no. ) All Mesons are Unstable + & have a Baryon Number B=0
whats the deal with Pions ( Pi - Mesons ) 2 they are the lightest Mesons , u get 3 different version with different electric charges - Pi to the + , to the -, & to the 0
when do u get loads of Pions in high En particle collisions ( like those studied at the CERN particle accelerator )
whats the deal with Kaons ( K - Mesons ) in reference to Pions 2 + what sorts do u get are Heavier & more Unstable than Pions , u get different ones like K to the + & K to the 0
whats the deal with their lifetime + what do they decay into Kaons = very short lifetime + decay into Pions
Kaons app have a unexpectdely long lifetime cos they have a S......... Quark Strange
What were discovered in C...... r..... , & so C..... r..... S....... are a source of both particles, u can observe the tracks of these particles with a c....... c......... Pions & Kayons Cosmic Rays Cosmic Ray Showers Cloud Chamber
...... in....... with ..... via the Strong Force Mesons Interact Baryons ( Pions interactions swap Ps with Ns & Ns with Ps, but leave the overall Baryon no. unchanged )
whats the deal with Letpons ( eg Es & Neutrinos ) 2 + wb exchange particles - fundamental or not? they dont feel the SNF, Theyre Fundamental Particles, (exchange particles also come under theh branch of 'fundamental particles')
they only really i...... with other p...... via the W..... interaction , ( along with a bit of gravitational force & the EM force as well if theyre charged ) interact particles weak
Es are s..... & very familiar , but there = also other L....., such as the M.... ( symbol), that are just like h...... Es stable Leptons Muons heavy
whats the deal with Muons 2 they = Unstable , & decay eventually into Ordinary Es
The E. & Muon L..... each come with their own n...... , Ve & V ( small Muon symbol ) Lepton neutrino
whats the deal with Neutrinos 2 + what sort of interaction do they ONLY take part in they have 0 or almost 0 mass & 0 electric charge ( so they dont do much) Weak Interactions
Like the Baryon no. , the Lepton no. is just the no. of Leptons, Each Letpon = Lepton no. = +1, But u have to count the TYPE of Lepton seperately, so the E & Muon type of Lepton have to be counted seperately , u get different Lepton numbers, Le & L ( small Muon symbol ) look on Board for all the no. , charge stuff
Quarks:
Quarks are f.......... particles, what are Quarks the building blocks for (the fundamentals for) fundamental, Quarks = the building blocks for Hadrons ( baryons & mesons )
what are the AntiParticles of Hadrons made from AntiQuarks
how many types of Quarks dyu need to make Ps & Ns + what are they only 2 types, the up Quark (u) & the down Quark (d)
An extra one called the S...... quark (s) lets u make m.... particles with a property called s............. Strange more Strangeness
Strangeness is only c........... some of the time, Strangeness, like B....... no., is a q..........number - it can only take a certain set of values Conserved Baryon Quantum
Strange Particles eg kaons are created via what force + decay via what other force Strange Particles = Created via the Strong Interaction + Decay via the Weak Interaction
tho in which of those 2 interactions is Strangeness conserved & which one is it not conserved in Strangeness = conserved in the Strong Interaction , But not in the Weak interaction
This means Strange P....... are Always produced in p....... ( eg K to the +, & to the -), one has a strangeness of +1, & the other = Strangeness of -1, so overall Strangeness of 0 = Conserved Particles Pairs
How many Quarks are Baryons made from 3 Quarks
from what did Evidence of Quarks come from ( Learn the charges for each u d s for both anti & normal, also on the board is the Combination of Quarks that u need to know for both Ps, Ns & their Antis, yes u guessed it there Anti-make up of Quarks is the opposite charge ) Evidence for Quarks came from hitting Ps with high- En Es
^^ what did the way the Es scattered show that there were 3 concentrations of charge (quarks) Inside the P.
M..... consist of a Q..... & an A...... Mesons Quark AntiQuark
whats the deal with what Pions are made from Pions = made from combinations of Up, down, Anti-up & Anti-down Quarks
Kaons have s........... so u need to put in s Quarks as well , whats the Strangeness value of an s Quark Strangeness -1
For the following Mesons, tell me their Quark & Anti-Quark composition + also their Strangeness value :
K to the 0 (kaon) d & anti-S S = +1
K to the + u & anti-S S = +1
Pi to the + (pion) u & anti-d S=0
Pi to the 0 2 u & anti-U , d & anti-down S=0
Pi to the - d & anti-U S=0
Anti-K to the 0 s & anti-d S = -1
K to the - s & anti-U S = -1
The Pi to the - meson is just the AntiParticle of the Pi to the + Meson , the K to the - Meson is just the AntiParticle to the K to the + Meson
And the Antiparticle of the Pi to the 0 meson is itself (N-udd, P-uud)
The w...... I...... is smthn that Changes Q...... t....... Weak interaction Quark type
In Beta Minus decay , whats changed into what else a N. = changed into a P.
^^ how do u say that in terms of Quarks udd changes into uud ( if u look at the charges for it .... it works, it goes from a Neutron when the udd Quarks added to 0 , to a P. where they add to 1, which = overall P. charge!
Some U........ I......... like Carbon-11 decay by Beta Emission, in this case what happens a P. changes to a N., so u get a u Quark changinig to a d quark ( & so that changes the Quark charge to = the charge of a N. )
How many properties are conserved in Particle Interactions .4
C.... is always conserved, in Any particle interaction, the t..... c.... after the interaction must equal the total charge before the Interaction Charge Total Charge
B..... no. is always conserved, Just like with charge, in Any particle interaction, the Baryon no. after the int. must = the baryon no. before the int.
Conservation of Lepton no. is a bit more complicated, ! The d........ types of Leptons have to be conserved S......... different Seperately
Theres no such thing as a f.... Quark free
if u blasted a P. with enuf En cud u seperate the Quark? Nope, whatd happen to the En The En of it wud just het changed into more Quarks & Anti-Quarks
^^ its P... P......... again & u just make M..... Pair Production Mesons ( Mesons cos theyre only made up of a Quark & Anti-Quark )
