Which of the following detectors is used to detect light intensities which are very weak?
A. Photomultiplier tube
B. Photovoltaic cell
C. Photoemissive tubes
D. Photo reflector
Answer:A
Which of the following detectors is used to detect light intensities which are very weak?
A. Photomultiplier tube B. Photovoltaic cell C. Photoemissive tubes D. Photo reflector
Explanation: PMT is used for detection of light intensities which are weak. As the name suggests, Photomultiplier tube multiplies the incident electrons using dynodes causing an avalanche of electrons.