P7

Question 1

What are the products of nuclear fission?

Answer 1

-2/3 high-speed neutrons
-Energy, in the form of gamma radiation

Question 2

How are nuclei contained in a fusion reactor?

Answer 2

By a magnetic field

Question 3

What is the major source of background radiation?

Answer 3

Radon gas, emitted by rocks deep underground

Question 4

List some sources of background radiation:

Answer 4

-Naturally-occurring unstable isotopes
-Cosmic rays
-Nuclear weapons
-X-ray machines

Question 5

What is induced fission?

Answer 5

Nuclear fission that occurs when a radioactive nucleus (uranium-235 or plutonium-239) absorbs a neutron

Question 6

How can radiation be used in medicine?

Answer 6

-To treat cancer
-To sterilise equipment
-To image inside the body

Question 7

Why do medical tracers have short half lives?

Answer 7

So that they do not stay radioactive long enough to become a health hazard

Question 8

What are some advantages and disadvantages of using radiation to sterilise medical equipment?

Answer 8

-Can be sterilised without high temperatures
-Can kill bacteria on materials susceptible to melting

-May not kill all bacteria
-Exposure could damage DNA