4.2.4 ionising radiation 4.2.2 types of radiation emissions Flashcards
Ions
Ions are particles that become charged by gaining or losing electrons. In the body , they react in an unusual way and may cause mutations that can also cause cancer.
Ionising radiation
They can break molecules into particles called ions
Gamma radiation
Are waves of electromagnetic radiation released by the nucleus. They penetrate far into materials without being stopped and will travel a long-distance through the the air. This means that they are weakly ionising because they tend to pass through rather than collide with particles. This suggest that they cause less damage than alpha or beta radiation. They are stopped by metres of lead or concrete.
Beta radiation
Beta particle are simply a fast-moving electron released by the nucleus. They have no mass. They are moderately ionising and penetrate moderately far into materials before colliding. They are stopped by sheet of aluminium. when a beta particle is emitted, a neutron in the nucleus has turned into a proton.
Alpha radiation
Is when an alpha particle is emitted from the nucleus. They contain 2 protons and 2 neutrons.they don’t penetrate vey far into materials as their size is strongly ionising. They cause a lot damage , but they are stopped by a sheet of paper.
What are the charges of ionising radiation
1) alpha charge= +2. Mass= 4.
2) beta charge= -1. Mass= negligible
3) gamma charge= 0. Mass= 0.
Smoke detectors - alpha radiation
. A radioactive material fires alpha particles at a smoke detector.
. If there is smoke between the radioactive material and the smoke detector, then less alpha particles will reach the detector. Which will set off the smoke alarm
Paper production- beta radiation
. We can fire beta particles through paper in a factory to make sure that the paper being produced is the right thickness.
. If the thickness of the paper changes, more or less beta particles will reach the detector. Production can then be stopped.
Sterilisation - gamma radiation
. We can use gamma radiation to sterilise medical equipment in hospitals. Sterilisation kills bacteria and viruses.
Exploring internal organs - gamma radiation
. If we put a gamma emitting isotope into a patients’s body. We can trace the radiation’s movement around the body.
. Gamma radiation is the most penetrating type of radiation. This means it can pass through objects more easily than alpha or beta radiation. This mean gamma can leave the body without creating too much damage (ionisation).
. Gamma radiation also has a short half-life. This means that the radiation vanishes quickly.