i wanted to know about first principal focus and second principal focus .
Asked by Shagun Rastogi | 14th Mar, 2015, 07:05: PM
First principal focus:
First principal focus of a lens is that point on the principal axis of the lens at which if an object is placed, the image would be formed at infinity.
It is denoted by F1.
Answered by Faiza Lambe | 16th Mar, 2015, 09:49: AM
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