quiz 24 Flashcards
What is count rate?
number of decays per second recorded by a detector
State the unit of activity
bequerels, bq
When writing the symbol for an beta particle what numbers go at the top and bottom?
top=0 bottom=-1
An alpha particle is the same as a nucleus of what element?
Helium
What are 2 sub-atomic particles found in the nucleus
proton and neutrons
When a gamma ray is emitted from a nucleus what happens to the atomic number and mass number
no change
When radiation is emitted from an unstable nucleus, what is the resulting nucleus called?
daughter nucleus
Which of alpha,beta and gamma is the most penetrating?
gamma
How can an electron move to a higher energy level?
electrons absorbs electromagnetic radiation
Which of alpha,beta and gamma is the least ionising?
gamma
What can happen to an electron when it emits electromagnetic radiation?
moves to a lower energy level
Which of alpha,beta and gamma is the most ionising?
alpha
What is an alpha particle?
2 protons and 2 neutrons
State the range in air of alpha
5cm
What can gammma stopped by?
thick concrete or lead
