Question

What is principal focus ??

Answer 1

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$\Large\fbox{\color{purple}{QUESTION}}$

WHAT IS PRINCIPAL FOCUS ?

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$\Large\fbox{\color{purple}{ SOLUTION }}$

principal focus is a point in principal axis where all the reflected rays either diverged or CONVERGED

principal focus is represented by ‘ f ’ which which is half of the centre of curvature

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Answer 2

Answer:

Principal focus is the point on the Principal Axis where all the light rays after reflection or refraction meet or appear to meet.