leptons 2.2.4

Question 1

what are leptons

Answer 1

are a group of fundamental particles
(they are not made up of any other particle)

Question 2

what force interacts on leptons

Answer 2

they interact with other particles by the weak force (mainly), gravitational force (sometimes, and EM force (if they are charged)

———> they DO NOT interact via the strong nuclear force

Question 3

what are the most common leptons (state their symbols)

Answer 3

-electron (e-)
-electron neutrino (Ve)
-muon (μ−)
-muon neutrino (Vμ)

Question 4

what are the most abundant leptons in the universe

Answer 4

neutrinos (they have no charge and negligible mass)

Question 5

what charge do electrons and muons have

Answer 5

-1e

Question 6

why arnt quarks classified as leptons if they are a fundamental particle

Answer 6

leptons DO NOT interact with strong force, whilst quarks do

Question 7

what is lepton number

Answer 7

Quantum number and is conserved in all interactions
-the number of leptons in an interaction (L)
-it depends on whether the particle is a lepton, anti-lepton or neither

Question 8

what is the lepton number of a lepton

Answer 8

L = +1

Question 9

what is the lepton number of an anti -lepton

Answer 9

L = -1

Question 10

describe muon decay

Answer 10

-muons are slightly heavier than an electron
-muons (μ−) typically decay into an electron
-anti-muons (μ+) decay into positrons
muon decay occurs via weak interaction