Extra TopicsTopic Summary
Topic Summary: Radiation Detection
Part of Radiation Detection — GCSE Physics
This topic summary covers Topic Summary: Radiation Detection within Radiation Detection for GCSE Physics. Revise Radiation Detection in Extra Topics for GCSE Physics with 13 exam-style questions and 11 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 12 of 12 in this topic. Use this topic summary to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 12 of 12
Practice
13 questions
Recall
11 flashcards
Topic Summary: Radiation Detection
Key Terms
- GM tube — ionisation-based counter for count rate
- Count rate — detections per minute/second
- Film badge — cumulative dose monitor for workers
- Cloud chamber — makes particle tracks visible
- Ionisation — removing electrons from atoms
- Activity — decays per second (becquerels)
GM Tube Mechanism
- Radiation enters through thin mica window
- Ionises argon gas inside tube
- Ions accelerated by high voltage
- Movement of ions = current pulse
- Each pulse counted by electronic counter
Cloud Chamber Tracks
- Alpha: thick, straight, short tracks
- Beta: thin, wiggly, longer tracks
- Gamma: no tracks (no charge)
- Tracks = vapour condensing on ions
Film Badge Layers
- Open window: all radiation
- Plastic: blocks alpha, lets beta+gamma through
- Aluminium: blocks alpha+beta, only gamma
- Darker film = higher dose received
- Different windows identify radiation types