Question

Hi friends i passed 9 class
I scored 2 rank in my class by 95.18 %

And now i am in 10 class
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What is the definition focal length ​

Answer 1

Explanation:

●The distance between the centre of a lens or curved mirror and its focus.

●The equivalent distance in a compound lens or telescope.

Answer 2

Explanation:

the distance between the centre of a lens or curved mirror and its focus.

the equivalent distance in a compound lens or telescope.