P7.4 - More About Alpha, Beta And Gamma Radiation (Finished)

Question 1

How do you measure the absorption of materials for radiation?

Answer 1

1) Count radiation using a geiger counter from the source.
2) measure without source to get bg radiation
3) subtract bg from bg+source to get just source
4) or add material and measure than subtract from bg+source

Question 2

What does an object being irritated mean?

Answer 2

irritated, not radioactiveIt means the object is exposed to radiation

Question 3

What is radioactive contamination?

Answer 3

If unwanted radioactive atoms get onto or into an object it is said to be contaminated

Question 4

Irritating something does not make it ___

Answer 4

Radioactive

Question 5

How can you reduce the effects of irritation?

Answer 5

By keeping objects in lead-lined boxes, standing behind barriers, being in different rooms etc

Question 6

Why is contamination dangerous?

Answer 6

Contamination atoms may decay releasing harmful radiation, which is especially dangerous if radioactive particles get inside your body

Question 7

How can you prevent contamination?

Answer 7

To prevent contamination gloves or tongs could be used when handling sources, protective suits could be used

Question 8

Why is ionisation harmful to cells?

Answer 8

Ionisation in a loving cell can damage or kill it. Also genes can be damaged causing cancer

Question 9

How can workers who use ionising radiation reduce their exposure?

Answer 9

X keeping as far away as possible from the source

- spending little time in high risk areas

Question 10

Why are beta and gamma sources most dangerous outside the body?

Answer 10

Beta and gamma sources can penetrate the body and get to delicate organs. Alpha can’t penetrate skin and is easily blocked so it is less of a danger

Question 11

Why is alpha radiation the most dangerous inside the body?

Answer 11

Alpha sources inside the body do all their damage in a very localised area, with beta radiation is absorbed over a wider area and some passes out and gamma sources mostly pass straight out

Question 12

How do smoke alarms work?

Answer 12

Smoke alarms have a radioactive isotope that sends out alpha particles into a gap in the circuit. They ionise the air allowing a current to pass across that gap, but smoke absorbs the particles stopping the current so the alarm sounds

Question 13

How does thickness monitoring in foil production work?

Answer 13

A radioactive source sends out b radiation, the amount of b passing through depends on the thickness, if it is too thick the detector reading drops a signal is sent to increase roller pressure