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The figure below shows the features of a Geiger-Muller (G.M) Tube used for detecting radiation.

The figure below shows the features of a Geiger-Muller (G.M) Tube used for detecting radiation.
pic27920191330.png
(i) State the use of Argon gas and Bromine.
Argon gas
Bromine
(ii) Explain how radiation from the source is detected by the tube.
(iii) State one use of radio activity in medicine.

Answers


sharon
(i) Argon gas – ionized by the radiation.
Bromine – quenching agent.
(ii)
- When a radioactive substance is placed in front of the window, the emitted radiations enter the tube through the window and ionize the argon gas.
- The negative ions move towards the anode while the positive ions move towards the cathode.
- As ions accelerate, they collide with more particles on their paths, resulting in further ionization (Avalanche of electrons).
- A pulse current flow. A corresponding pulse voltage is registered across the resistor R.
- These currents can be amplified and if passed through a loudspeaker, clicks are heard – or a rate meter.
(iii)
- Used to monitor the function of thyroid gland.
- Used to trace blood clots.
- Used to kill harmful tissues such as cancerous cells.
sharon kalunda answered the question on September 27, 2019 at 10:36

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