Radioactivity Flashcards
All nuclear reactions and their origin explained.
What is radioactivity?
The process by which unstable nuclei emits radiation in form of energy in inorder to attain stability
Why do nuclei undergo radiation?
Inorder to attain stability
What is a nuclide?
A specific combination of protons and neutrons in a nucleus.
What is the strong nuclear force?
It’s a force that holds the nucleons together in the nucleus.
How can an unstable nucleus be made stable?
By adding more neutrons to it
What are the two families that sub-atomic particles are divided into?
Hadrons and Leptons
What are hadrons?
Particles in the nucleus affected by the strong nuclear force.
What are Leptons?
Particles in an atom not affected by the strong nuclear force
Give two examples of Leptons.
Electrons and neutrinos
Give two examples of hadrons.
Protons and neutrons
What are the fundamental particles from which hadrons are made from?
Quarks
Name three basic types of quarks.
Up (u), down (d) and strange (s)
What are the two types of hadrons?
Baryons and mesons
How many quarks make up baryons?
3
How many quarks make up mesons?
2
What are the quark combination that make up a proton?
Two up quarks and one down quark
What are the quark combination that make up a neutron?
Two down quarks and one up quark
What are the quark combination that make up a pi(+) meson?
One up quark and one down anti quark
What are the quark combination that make up a phi meson?
One strange quark and one anti strange quark
What are the three types of radiation emitted from radioactive substances?
Alpha, beta and gamma radiation
What are the two types of beta radiation?
Beta-minus and beta-plus radiations
What is a beta-minus radiation?
It is simply an electron with a charge of -e
What is beta-plus radiation?
This radiation in the form of positrons, similar to electrons in terms of mass but with positive charge +e.
What happens when a particle collides with its anti-matter particle?
A gamma ray photon is emiited
Explain how a beta-minus decay comes about.
In this decay a neutron from the nucleus is changed into a proton and an electron, a particle known as an anti neutrino is produced in the process.
Explain how a beta-plus decay comes about?
In this decay a proton changes into a neutron and an electro neutrino is released.
True or false, is nucleon number and proton number conserved in decay processes?
True
True or false, instead of saying that mass is conserved in decay processes we have to say that it’s mass-energy which is conserved?
True
To which family of fundamental particles do electrons and neutrinos belong to?
Leptons
How does a neutron become a proton in beta-minus decay?
One of the down quark in the neutron changes to an up quark
How does a proton become a neutron in beta-plus decay?
One up quark in the proton changes to a down quark
What is the weak nuclear force?
This is the force that acts on both quarks and Leptons
What force is responsible for beta decay?
The weak interaction
Relate ionisation to radiation.
Radiation affects the matter it passes through by causing ionisation. Alpha radiation is the most strongly ionising because of its larger mass and charge and it usually travels very slow. Then followed by beta radiation and lastly gamma radiation because it has no charge and travel very fast
What is the behaviour of the three types of radiation in an electric field?
Since alpha radiation is positively charged it is attracted towards the negative charge of the field and beta-minus is attracted towards the positively charge of the field, beta-plus is attracted towards the negative charge of field and the gamma radiation is undeflected in the field because of no charge.
What is the most penetrating radiation?
Gamma radiation
True or false, can gamma radiation be completely absorbed by lead?
No, lead only reduces the intensity of the radiation, it would need an infinite amount of lead to completely absorb the gamma radiation
What is an electron volt?
This is the amount of energy transferred when an electron travels through a potential difference of one volt
One electron volt is equal to how many joules of energy?
1.6×10^-19 joules of energy
True or false, You’re bullshiass?
True
