Correct Answer
Correct answer is Nuclear radiation ionizes gas in a tube
Step-by-step explanation:
Geiger counters is used to detect radioactive emissions such as beta particles and gamma rays. Geiger counter consists of a tube inside this tube an inert gas is filled that becomes conductive of electricity when it is impacted by a high-energy particle. When a Geiger counter is exposed to ionizing radiation, the particles penetrate the tube and collide with the gas atoms and ionize them due to which more electrons are released. Positive ions exit the tube and the negatively charged electrons gets attracted to a high-voltage middle wire. When the number of electrons which is collected around the wire reaches a threshold, it creates an electric current. This causes the temporary closing of a switch and generates an electric pulse which get registered on a meter.