Radiation Flashcards
What is nuclear radiation?
A radioactive element which emits radiation from the nucleus.
What does the Atom contain?
Protons, Neutrons and Electrons
What are the main types of Nuclear Radiation?
Alpha, Beta & Gamma
What is a Alpha Particle?
A helium nucleus that has two protons and two neutrons and has a large mass and is postively charged.
What is a beta Particle?
A high-speed electron that has a very small mass is negatively charged.
What are Gamma Rays?
High energy Electromagnetic waves.
How much ionsation does each type of nuclear radation do.
Alpha - most - Beta - Middle - gamma Least
How pentrating is each type of radation?
Alpha - Least Beta - Middle Gamma rays - most
What can alpha particles be stopped by?
A sheet of paper
What can beta particles be stopped by?
a few millimetres of Thin aluminium
What can gamma rays be stopped by?
Several Centimetres of Lead
What is the definition of Activity of a source?
The number of nuclei which disintegrate in one second.
What is the Unit for Activity (A)
Becquerels (Bq)
What are 3 natural sources of background radation?
cosmic rays from space - the body - some foods such as bananas
What are 2 artificial sources of background radation?
fallout from nuclear weapons testing and radioactive waste from nuclear power stations
What is absorbed dose?
energy absorbed per unit of mass
What is the unit for Absorbed Dose?
Grays (Gy)
What is Equivelent Dose?
The measure of the biological effect of radiation
What is the unit for equivalent dose?
Sieverts (Sv)
What is the annual effective dos limits for the general public and radiation workers?
1 mSv per year for general public - 20mSv per year for radiation workers
What is Equivalent dose rate?
The equivalent dose recieved per unit of time.
What are 3 applications of nuclear radiation?
Radiotherapy, Sterilisation, Radioactive tracers
