COMEDK · Physics · 25. Ray Optics
A convex and a concave lens separated by distance \(d\) are then put in contact. The focal length of the combination
- A decreases
- B increases
- C becomes zero
- D remains the same
Answer & Solution
Correct Answer
(A) decreases
Step-by-step Solution
Detailed explanation
Let \(f_{1}\) and \(f_{2}\) are focal lengths of convex and concave lens respectively, when they are kept in contact co-axially, then focal length \(F\) of the combination is given as…
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