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The focal length of a coverging lens is ...

The focal length of a coverging lens is measured for violet,green and red colours.It is `f_v,f_g` and `f_r` respectively.We will get

A

`f_v=f_g`

B

`f_ggtf_r`

C

`f_vltf_r`

D

`f_vgtf_r`.

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MODERN PUBLICATION-UNIT TEST -06-EXERCISE
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