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Focal length of a plane mirror is...

Focal length of a plane mirror is

A

positive

B

negative

C

zero

D

infinity

Text Solution

Verified by Experts

The correct Answer is:
D
In case of a plane mirror, the image is formed as far behind the mirror as the object is in front of it.
`therefore` u=-v
`1/(f)=1/(u)+1/(v)`
`=-1/v+1/v=0`
`therefore f=1/0=oo`
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