particle physics

Question 1

define alpha decay

Answer 1

the process of an unstable nucleus emitting an alpha particle to become more stable

Question 2

define annihilation

Answer 2

the process of a particle and its antiparticle colliding and being converted into energy. the energy is released into two photons to conserve momentum

Question 3

define antiparticle

Answer 3

corresponding antiparticle to a particle with same mass but opposite charge and conservation numbers

Question 4

define baryon number

Answer 4

a quantum number that is conserved in all particle interactions.

Question 5

define baryon

Answer 5

a type of hadron, made up of 3 quarks

Question 6

what is the only stable baryon?

Answer 6

proton

Question 7

define beta-minus decay

Answer 7

the process of a neutron inside a nucleus turning into a proton, and emitting a beta-minus particle (electron) and a neutrino

Question 8

define beta-plus decay

Answer 8

the process of a proton inside a nucleus turning into a neutron and emitting a beta-plus particle (proton) and a neutrino.

Question 9

define electron diffraction

Answer 9

the spreading of electrons as they pass through a gap similar to the magnitude of their wavelength. (de Broglie)

Question 10

define electron - volt

Answer 10

the work done to accelerate an electron through a potential difference of 1V.

Question 11

define energy levels

Answer 11

defined and distinct energies at which electrons can exist in an atom.

Question 12

define excitation

Answer 12

the process of an electron taking in exactly the right quantity of energy to move to a higher energy level

Question 13

define gauge boson

Answer 13

the exchange particles that transmit the four fundamental interactions between particles

Question 14

define ground state

Answer 14

the lowest, most stable energy level that an electron can exist in

Question 15

define hadrons

Answer 15

a class of subatomic particle that experiences the strong nuclear interaction

Question 16

define ionisation

Answer 16

the process of an atom losing an orbital electron and becoming charged

Question 17

define isotope

Answer 17

an atom of an element with the same number of protons but different numbers of neutrons

Question 18

define isotopic data

Answer 18

data from isotopes that can be used for a purpose, such as carbon dating

Question 19

define kaon

Answer 19

a type of meson that decays into pions

Question 20

define lepton number

Answer 20

a quantum number that is conserved in all particle interactions. both electron lepton numbers and muon lepton numbers must be conserved

Question 21

define lepton

Answer 21

a group of elementary subatomic particles, consisting of electrons, muons and neutrinos

Question 22

define meson

Answer 22

a class of hadron that is made of a quark and antiquark pair

Question 23

define muon

Answer 23

a type of lepton that decays into electrons

Question 24

define neutrino

Answer 24

a subatomic particle whose existence was hypothesised to maintain the conservation of energy in beta decay

Question 25

define nucleon number (A)

Answer 25

the sum of the number of protons and neutrons in a given nucleus

Question 26

define nucleon

Answer 26

a proton or neutron

Question 27

define pair production

Answer 27

the process of a high energy photon converting into a particle and its corresponding antiparticle.

Question 28

define photon

Answer 28

a packet of energy

Question 29

define pion

Answer 29

a type of meson and the exchange particle for the strong nuclear force

Question 30

define positron

Answer 30

electron antiparticle

Question 31

define proton number (Z)

Answer 31

the number of protons in a given nucleus

Question 32

define stopping potential

Answer 32

the minimum potential difference required to stop the highest KE electrons from leaving the metal plate in the photoelectric effect

Question 33

define strange particles

Answer 33

particles produced through the strong interaction that decay through the weak interaction

Question 34

define strong nuclear force

Answer 34

a force that acts between nucleons in a nucleus to keep it stable

Question 35

what is the range of the strong nuclear force

Answer 35

attractive at distances up to 3fm, repulsive under 0.5fm

Question 36

define threshold frequency

Answer 36

the minimum frequency of photons required for photoelectrons to be emitted from the surface of a metal plate through the photoelectric effect

Question 37

what is the threshold frequency equal to?

Answer 37

the metals work function divided by Planck’s constant

Question 38

define work function

Answer 38

the minimum energy required to remove an electron from a metal’s surface