Two thin lenses of focal lengths f 1 and f 2 are in contact and coaxial. The power of the combination is :
A
B
C
D
Text Solution
Verified by ExpertsThe correct answer is:
D
If two thin lenses of focal lengths f 1 , f 2 are placed in contact coaxially, then equivalent focal length of combination is
= 
= 
Power for the combination is
P = 
= 
= 
Prepare Smarter with CGP Edu
Get practice questions, solutions, and test series in one place.
Write a Review
Share your experience with this question and solution.
Commentary
Send your comment, doubt, correction, or feedback to admin.
Similar Questions
Explore conceptually related problems
A convex lens of focal length 25 cm and a concave lens of focal length 20 cm are mounted coaxially …
A convex lens of power 4D and a concave lens of power 3D are placed in contact, the equivalent powe…
Two thin lenses of power +5D and –2D are placed in contact with each other. Focal length of the com…
The focal length of a plano-concave lens is – 10 cm, then its focal length when its plane surface i…
A combination of two thin lenses with focal lengths f 1 and f 2 respectively forms an image of dist…
A plano convex lens (f = 20 cm) is silvered at plane surface. Now f will be