what are photographic plates ? why are they used radioactivity experiments?
What did you find when you did a Google search for "photographic plate" and what don't you understand about it?
google explain it in terms of photography, a film used in that for imaging. i want to know why in every experiment of radioactivity these plates are taken.
Which experiments are these (at least some examples) and when (approximately) were they performed? What other technologies are you thinking of, as alternatives to photographic plates?
Scientists choose technologies for their experiments based on what is available at the time, and their advantages and disadvantages.
"In the discovery of radioactivity. Henry becquerel placed some uranium with photographic plates"
and what was the result ?
I have done this experiment myself in years gone by
Photographic plates are ancient artifacts, typically consisting of glass sheets covered with a light-sensitive emulsion; upon exposure to light, the emulsion becomes opaque.
I tried Google (which is always a good idea)_. This link came up in the top few of a very long result list for "Radiation Detectors History". Read it and you can be an 'expert' on the history of such things.
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