Practical Applications of Radiation
Physics: Edexcel IGCSE, topic 7.2.14
Practical Applications of Radiation
We can use alpha, beta, and gamma radiation for many practical purposes:
Smoke detectors - alpha radiation
- A radioactive material fires alpha particles at a smoke detector.
- If there is smoke between the radioactive material and the smoke detector, then less alpha particles will reach the detector.
- This will set off the smoke alarm.
Paper production - beta radiation
- We can fire beta particles through paper in a factory to make sure that the paper being produced is the right thickness.
- If the thickness of the paper changes, more or less beta particles will reach the detector. Production can then be stopped.
Exploring internal organs - gamma radiation
- If we put a gamma-emitting isotope into a patient’s body, we can trace (follow) the radiation’s movement around the body.
- Gamma radiation is the most penetrating type of radiation. This means it can pass through objects more easily than alpha or beta radiation. This means gamma can leave the body without creating too much damage (ionisation).
- Gamma radiation also has a short half-life. This means that the radiation vanishes quickly.
Sterilisation - gamma radiation
- We can use gamma radiation to sterilise medical equipment in hospitals. Sterilisation kills bacteria and viruses.
- We can also use gamma rays to sterilise food.
Carbon dating - beta radiation
- When a living organism dies, it contains a certain amount of the radioactive substance carbon-14.
- Carbon-14 emits beta radiation with a known half life.
- Therefore, the emission rate will reflect the age of the fossil or rock.
- The older the fossil, the lower the emission rate.
- The younger the fossil, the higher the emission rate.
Test yourself on Practical Applications of Radiation
How does a smoke detector work?
Which of the following is true about applications for ionising radiation?
How is blood flow in the body imaged using radiation?