I read this tip of Physics P6 Can somebody tell me how to do that or perform it
"know how to arrange a set square either side of a cylinder/sphere to measure diameter"
One more tip was there which said
in light experiments using objects, lenses and a screen
try to use a translucent screen
but why
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?
One more tip was when measuring an interval of time explain how to use a fiducial aid at the centre of the oscillation
I dont know.............
Thx