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A combination is formed by keeping a con...

A combination is formed by keeping a convex lens in contact with a concave lens. If both have same focal length of value 25 cm, then power of combination is ...... D.

A

50

B

infinite

C

zero

D

25

Text Solution

Verified by Experts

The correct Answer is:
C
`1/f=(1)/(f_1)+(1)/(f_2) =(1)/(25)-(1)/(25)`
`1/f=0`
`therefore` Power P=`1/f=0`
`therefore P=0`
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