[AS] Particles and Radiation Flashcards
What constituents make up the nucleus?
Proton, Neutron
What is the charge on a proton?
+1.6 x 10^-19 C
What is the charge on a neutron?
None
What is the charge on an electron?
-1.6 x 10^-19 C
What is specific charge referred to as in the formulae booklet?
Charge-to-mass ratio
In AZX notation, what does X refer to?
The element
In AZX notation, what does Z refer to?
Proton number
In AZX notation, what does A refer to?
Nucleon number
What is an isotope?
A form of an atom with the same number of protons but a different number of neutrons
What are the four fundamental forces?
Gravity
Electromagnetic
Strong Nuclear
Weak Nuclear
What property of a nucleus necessitates the existence of the Strong Nuclear force?
Protons in a nucleus are positively charged; they should be repelled due to the Electromagnetic force
Up to what range is the strong nuclear force attractive?
3 fm
Closer than what range is the strong nuclear force repulsive?
0.5 fm
How much is a femtometer?
1 x 10^-15m
What is the proton number above which a nuclei becomes unstable and radioactive?
83
An alpha particle is the same as what?
A helium nucleus
A beta-minus particle is the same as what?
A high-speed electron
Other than a beta-minus particle, what else is emitted in beta-minus decay?
Electron-Antineutrino
What is a gamma ray?
A photon of electromagnetic radiation
Why was the presence of the neutrino first hypothesised?
Conservation of energy in beta decay
What is the order of the electromagnetic spectrum, in increasing frequency?
Radio, microwave, infrared, visible light, ultraviolet, X-ray, gamma ray
What properties are the same for a particle-antiparticle pair?
Mass, rest energy
What property is opposite for a particle-antiparticle pair?
Charge
What is pair production?
A photon with enough energy turns into a particle and an antiparticle
Why are particle tracks in pair production curved?
There’s usually a magnetic field present in experiments, and they have opposite charges
What is the only type of photon with enough energy for pair production?
Gamma ray photon
What pair is usually created in pair production, an why?
Electron-positron, because they have relatively low mass
What is the minimum energy for a photon to undergo pair production equal to?
Total rest energy of the particles produced (2E0)
What happens when a particle meets its antiparticle?
Annihilation
How long to antiparticles typically exist for?
A fraction of a second
What do you multiply eV by to get Joules?
1.6 x 10^-19
What do you multiply MeV by to get Joules?
1.6 x 10^-13