NRRPT Detection and Measurement 2

Question 1

Which detector type operates on the principle of collecting ion pairs produced by radiation in a gas-filled chamber?

Accepted Answer

Ionization chamber

Answer

Scintillation detector

Answer

Thermoluminescent dosimeter

Answer

Semiconductor detector

Question 2

A Geiger-Mueller tube operating in the 'plateau' region of its voltage-response curve indicates:

Accepted Answer

Optimal operating voltage where count rate is stable despite small voltage variations

Answer

The tube is saturated and no longer counting accurately

Answer

The tube has entered proportional counting mode

Answer

The applied voltage is too low to detect radiation

Question 3

What is the primary advantage of a NaI(Tl) scintillation detector over a GM tube for gamma spectroscopy?

Accepted Answer

Ability to discriminate photon energies and perform spectroscopy

Answer

Higher sensitivity to alpha particles

Answer

Lower cost and simpler electronics

Answer

Better performance in high radiation fields

Question 4

The 'dead time' of a radiation detector refers to:

Accepted Answer

The period after a count during which the detector cannot register another event

Answer

The time required for the detector to warm up before use

Answer

The time between battery replacements

Answer

The delay before the detector's display updates

Question 5

A thermoluminescent dosimeter (TLD) measures absorbed dose by:

Accepted Answer

Measuring light emitted when heated crystals release stored energy

Answer

Counting electrical pulses generated by ionization

Answer

Detecting changes in chemical composition of a film emulsion

Answer

Amplifying ionization current with a photomultiplier tube

Question 6

Which detector is most appropriate for measuring neutron dose equivalent in a mixed neutron-gamma field?

Accepted Answer

Proportional counter with BF3 or He-3 fill gas

Answer

Standard GM tube

Answer

NaI(Tl) scintillator

Answer

Silicon PIN diode

Question 7

When calibrating a survey meter, the calibration factor is applied to correct for:

Accepted Answer

Differences between the detector's actual response and the displayed reading

Answer

Battery voltage fluctuations during measurement

Answer

Temperature changes in the measurement environment

Answer

Distance from the radiation source to the detector