99-100 - Radiation Flashcards
What is an isotope?
An element with a different number of neutrons (different mass)
Why are isotopes often radioactive?
They have unstable nuclei so they decay
What do we mean when we say that radioactivity is random?
There is no way to know or affect when nuclei will decay
What are the 6 main contributors to background radiation?
51% radon gas
14% rocks/building materials
12% food
12% medical treatments
10% cosmic rays
1% nuclear industry
What are cosmic rays?
The radiation from space (mainly the sun)
How does granite contribute towards someone’s dose of radiation?
Releases radon gas which remains in people’s homes
Why are pilots at a higher risk of some cancers?
High altitudes = more exposure to cosmic rays
Why are miners at a high risk of some cancers?
Rocks emit radiation
What do nuclear industry workers do to protect themselves?
Protective clothing
Face masks
Regular monitoring of radiation exposure
What do radiographers do to protect themselves?
Lead aprons
Lead screens
What are alpha particles made up of?
2 protons and 2 neutrons (helium)
How penetrating are alpha particles and why?
Not very penetrating - too big, heavy, and slow
How ionising are alpha particles?
Strongly
What does it mean to be ‘ionising’?
Knocking electrons from particles and creating ions
What materials can beta penetrate?
Thin paper
What are beta particles?
High speed electrons
How does beta radiation work?
A neutron is split into a proton and an electron in the nucleus
What does alpha decay do to an element’s mass and proton number?
Mass -4
Atomic number -2
What does beta decay do to an element’s mass and atomic number?
Mass - no change
Atomic number - +1
What is gamma radiation?
Short wavelength waves
How penetrating is gamma radiation?
Extremely - can only be stopped by materials such as lead
How ionising is gamma radiation and why?
Weak - the rays usually pass through without any collisions
Which types of radiation are deflected in magnetic fields?
Alpha and beta - alpha feels the greatest force but is deflected less
