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Assertion : The focal length of an equ...

Assertion : The focal length of an equiconvex lens placed in air is equal to radius of curvature of either face.
Reason : For an equiconvex lens radius of curvature of both the faces is same.

A

If both assertion and reason are true and reason is the correct explanation of assertion

B

If both assertion and reason are true but reason is not the correct explanation of assertion

C

If assertion is true but reasonb is false

D

If both assertion and reason are false.

Text Solution

Verified by Experts

The correct Answer is:
A
Both assertion and reason are true and reason is the correct explanation of assertion.
Assertion : Goggles have zero power. True
The focal length is given by `(1)/(f)=(mu-1)((1)/(R_(1))-(1)/(R_(2)))`. For goggle lenses, both sides are curved the same, `(1)/(f)=0` i.e., power is zero. Reason is also true and it is the explanation for the assertion.
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