1451Every Day ScienceMedium
Which one of the following elements the drum of a Photostat machine is made up of: _________?
ASelenium
BAluminium
CBarium
DNone of these
Correct answer
A. Selenium
Explanation
The photoreceptor drum in the heart of the system is basically a metal roller covered by a layer of photoconductive material. This layer is made out of a semiconductor such as selenium, germanium or silicon.