Uses Of Radioactivity

Question 1

What is irradiating food:

Answer 1

Food is exposed to gamma rays

Gamma rays kill microbes by ionising their DNA

This stops microbes from making the food go mouldy and makes it last longer

Question 2

What is sterilising medical equipment:

Answer 2

Equipment such as scales are exposed to gamma rays

Gamma rays kill microbes by ionising their DNA

Microbes will then not infect patients and cause disease

Question 3

Diagnosing cancer:

Answer 3

A tracer is injected into the person with cancer

Tracer collects at the location of cancer

Tracer contains a gamma source which can be detected by machines to show the locations and sizes of the tumours

Gamma sources are used as they can pass out of the body and be detected

Question 4

Treating cancer - radiotherapy:

Answer 4

Beams of gamma rays fired at cancer cells

This can kill the cancer cells by ionisation

Question 5

What are uses of radioactivity:

Answer 5

Irradiating food

Sterilising medical equipment

Diagnosing cancer

Treating cancer - radiotherapy

Smoke alarms

Question 6

Checking thickness of paper:

Answer 6

Beta particles sent through paper being made.

Thickness can be checked by measuring how much radiation gets through

More beta particles through paper = thinner paper

If it is too thin, the rollers can be adjusted to not roll as hard

Question 7

Checking for leaks in pipes underground:

Answer 7

Gamma source added to contents of pipe

Move a GM tube over the ground where the pipe is

Where there is a leak, there will be a higher count rate

Question 8

Smoke alarms:

Answer 8

Contain sources of alpha particles

Alpha particles ionise the air in between two charged plates

Ions move to an oppositely charged plate and create an electrical current