Detecting Radiation Flashcards

All 5 cards in this deck

How does photographic film detect radiation?

The film darkens (becomes fogged) when exposed to ionising radiation; the more radiation, the darker it becomes.

What does a Geiger–Müller tube connected to a counter measure?

The count rate — the number of radioactive emissions detected per second (counts/s).

Why is the background count measured before comparing the count rates of two radioactive sources with a GM tube?

So it can be subtracted from each reading, leaving the count rate due to each source alone.

True or false? When comparing two sources with a GM tube, the source–detector distance may be changed between the two measurements.

False. The distance must be kept the same for a fair comparison.

True or false? A Geiger–Müller tube can detect alpha, beta and gamma radiation.

True. It registers a count whenever any of these ionising radiations enters the tube.