(4) Uses of Radiation

Question 1

What is radioactive contamination?

Answer 1

The presence of unwanted radioactive nuclei on a material (you)

Question 2

What is irradiation?

Answer 2

The process of exposing material to nuclear radiation (can be used to kill bacteria or fungi)

Question 3

Name three sources of background radiation:

Answer 3

1) Natural rock
2) Cosmic rays from space
3) Fallout from nuclear weapons and nuclear accidents

Question 4

What unit measures radiation dosage?

Answer 4

Sieverts (Sv)

Question 5

What must you do when handling radioactive sources?

Answer 5

• use protective clothing
• Use tongs to keep distance
• minimise exposure time
• store sources in shielded containers

Question 6

Why does radiation exposure differ for different people?

Answer 6

• people who live locally to nuclear power stations or radiation testing
• people who work with radiation

Question 7

Why are isotopes with longer half lives more harmful?

Answer 7

They remain radioactive for much longer periods of time

Question 8

How is radiation used in medicine?

Answer 8

• examining internal organs
• sterilisation of equipment (with gamma)
• controlling/ destroying cancer

Question 9

What are medical tracers?

Answer 9

• a radioactive sources placed inside band object or person that can be tracked
• must have a short half life and decay into a stable isotope
• gamma radiation (weakly ionising)

Question 10

Why can’t alpha radiation be used?

Answer 10

The larger particle is highly ionising which means it could knock off electrons inside your body atoms, this could cause mutations or cancer