B1.31 - B1.35 Particles and radiation Flashcards
What are the three types of radiation?
Alpha
Beta
Gamma
What is ionising radiation?
Any form of radiation that interacts with matter resulting in ionisation of that matter.
What does an alpha particle consist of?
Two protons and two neutrons.
What gives the alpha particle it’s positive charge?
The two protons
Because alpha particles are relatively large, what does this mean they can do?
This means they can easily remove electrons from atoms when they collide with them.
How far can alpha particles travel in air?
1-2 CM
What can alpha particles be absorbed by?
A sheet of paper
Why is a beta particle high speed?
Because a high speed electron is ejected from the nucleus when a neutron turns into a proton.
How far can beta particles travel?
about 15cm in air
What can beta particles be absorbed by?
A sheet of aluminum about 5mm thick.
What can gamma rays by absorbed by?
Thick sheets of lead or several meters of concrete.
What is radioactive decay?
Random process that occurs when an unstable nucleus loses energy by giving out alpha or beta particles or gamma radiation.
What is half life?
The time taken for half the unstable nuclei in a sample to decay.
