Nuclear radiation Flashcards
Alpha
Also known as the nucleus of a helium atom. Positively charged, has a mass of 4 amu, has a slow relative speed and has a high ionising effect.
Beta
Also known as a high energy electron, negatively charged, fast moving, negligible mass, medium relative speed and medium ionising effect.
Gamma
Also known as a high energy/frequency wave, no charge, no mass, fast relative speed (speed of light) and low ionising effect.
What does the term ionisation mean?
Ionisation is the addition or removal of an electron from an atom to create an ion.
What is the ionising effect of Alpha radiation?
Alpha radiation is highly ionising.
What is the ionising effect of Beta radiation?
Beta radiation is moderately ionising.
What is the ionising effect of gamma radiation?
Gamma radiation is very weakly ionising.
What is the penetrating ability of Alpha radiation?
Alpha radiation is the least penetrating because they are the most ionising. Alpha particles are absorbed by 10cm of air 0.01mm of lead or a sheet of paper.
What is the penetrating ability of Beta radiation?
Beta particles are moderately penetrating. Their energy can be absorbed by 1m of air, 0.1mm of lead or 3mm of aluminium.
What is the penetrating ability of Gamma radiation?
Gamma rays have a very high penetrating ability because their ionising ability is so low. Their energy can ve absorbed by 1km of air or 10cm of lead.
What are some detectors of ionising radiation?
The Geiger-Muller Tube, photographic film and Scintillation Counter
What are the sources of background radiation?
Cosmic rays, radon gas, radioactive rocks, soil and plants, nuclear power stations and nuclear medicine.
What are some safety measures you can take when dealing with radiation?
Use safety glasses, keep it contained in a special shielded box after use, wash hands thoroughly and use plastic gloves.
What does the term activity mean?
The rate at which a radioactive source decays. It is measured in Becquerel (Bq).
What does the term half-life mean?
The half life of a radioactive source is the time for the activity to fall to half its original value.
What does the term absorbed dose mean?
The absorbed dose is the energy absorbed per unit mass of the absorbing material.
What does the equivalent dose mean?
The equivalent dose combines the absorbed dose with the radiation weighing factor to give a more accurate “picture” of the potential harm that could be done by radiation.
What is the radiation weighing factor?
The radiation weighing factor is a scale factor, which indicates the ability of a particular type of radiation to cause damage to living tissue.
What is the equivalent dose rate?
The equivalent dose rate is the amount of time exposed to the radiation, taking into account the amount of energy the radiation has and the type of radiation.
What are some applications of nuclear radiation in industry and medicine?
To help diagnose diseases or damage in the body with X-rays, external radiotherapy, internal radiotherapy, measuring the thickness of materials, radiography, tracers, sterilisation, dating and smoke detectors.
