Nuclear Physics Flashcards
Matter
Anything that has mass and takes up space.
Atom
Smallest unit of matter.
Background radiation
- nuclear weapons
- medicine
- radon gas from the ground
- cosmic rays
High frequency radiation
Ha the ability to break apart molecules specially DNA within cells. This causes cancer and is called ionizing.
Alpha decay
Alpha particle is two neutrons and two protons. They do not penetrate very far into materials, stopped by few cm of air. Because of their size they are strongly ionising. Can be written as helium nucleus.
Beta decay
Emits fast moving electron, so it doesn’t have mass. For every beta particle emitted, a neutron in the nucleus has turned into a proton. They are moderately ionising. They are absorbed by a sheet of aluminium.
Gamma decay
Gamma rays have a short wavelength of electromagnetic radiation. Weakly ionising, since they tend to pass trough rather than collide. They can penetrate far into materials, can travel a long distance trough air. Thick sheet of lead can stop it.
Unstable isotopes
Tend to decay into other elements and give out radiation as they try to become more stable.
Radioactive decay
Unstable isotopes try to become more stable, by giving out radiation. They try to balance the number of protons and neutrons in their nucleus or get rid of any excess energy.
Ionising radiation
Is radiation that knocks electrons off atoms, creating positive ions.
Ionising power
Of radiation source is how easily it can knocks electrons off atoms.
Nuclear equations (rule)
The total mass and atomic numbers must be equal on both sides.
