P2b Topic 6 - Using Radioactive Materials

Question 1

The levels of background radiation change depending on

Answer 1

.. Where you are

1) Certain underground rocks can cause higher levels of background radiation at the surface, especially if they release radioactive radon gas.
2) The radon concentration in people’s houses varies across the UK, depending on the type of rock your house is built on. The amount of radon gas people are exposed to also depends on the region of the country you live in.

Question 2

The half life of a radioactive isotope is the

Answer 2

Time taken for half of the undecayed nuclei to decay

Question 3

Food and equipment can be sterilised using

Answer 3

Gamma

Question 4

Irradiation is a particularly good method of sterilisation because

Answer 4

It doesn’t involve high temperatures so fresh fruit and plastic instruments can be sterilised without being damaged

Question 5

Medical tracers must use

Answer 5

Beta or gamma

Question 6

Beta radiation is used in

Answer 6

Thickness control

Question 7

Gamma rays can be used to

Answer 7

Treat cancer

Question 8

Ionising radiation can cause

Answer 8

Tissue damage and cell mutation

Question 9

Lower doses tend to

Answer 9

Cause minor damage without killing the cell. This can give rise to mutant cells which divide uncontrollably. This is cancer.

Question 10

Higher doses tend to

Answer 10

Kill cells completely. This causes radiation sickness if a lot of body cells get battered all at once.

Question 11

The extent of the harmful effects of ionising radiation depends on 2 things

Answer 11

A. How much exposure you have to the radiation.

B. The energy and penetration of the radiation.

Question 12

Outside the body

Answer 12

Beta and gamma sources are the MOST dangerous

Question 13

Inside the body

Answer 13

An alpha source is the MOST dangerous.

Question 14

How to protect yourself from radiation in a lab

Answer 14

1) Handle sources with tongs.
2) Keep source at arms length.
3) Point the source away from the body and don’t look at it.
4) Keep your exposure time short.
5) Store the source in a labelled lead box.

Question 15

How to protect yourself if you work with nuclear radiation

Answer 15

1) Wear a full protective suit.
2) Use lead lined suits, lead/concrete barriers and thick lead screens to prevent exposure to gamma rays.
3) Use remote control robot arms.

Question 16

What is vitrification

Answer 16

Melting down the nuclear waste to form a type of glass which can be stored inside steel canisters and buried underground

Question 17

Another way to deal with nuclear waste is by

Answer 17

Packing it into thick metal containers and/ or bury the waste in a deep hole and then fill the hole up with concrete.

Question 18

Some people worry that nuclear waste

Answer 18

Could leak out and pollute land, rivers and oceans.

Question 19

Nuclear power also carries the risk of

Answer 19

Leaks from the power station or a major catastrophe like Chernobyl.

Question 20

Positive of nuclear power

Answer 20

Very reliable resource
Reduces the need for fossil fuels
Clean source of energy
Huge amounts of energy can be generated from a relatively small amount of nuclear material
Nuclear fuel is cheap and readily available

Question 21

The overall cost of nuclear power is high due to the

Answer 21

Initial cost of the power plant and final decommissioning which takes decades

Question 22

Background radiation comes from

Answer 22

Air
Food
Building materials 
Rocks
Cosmic rays
Fallout from nuclear explosions 
Dumped nuclear waste