Question:medium
If a thin lens of focal length 20 cm is in contact with another lens of power 4 D, then the effective power of the combination is
If a thin lens of focal length 20 cm is in contact with another lens of power 4 D, then the effective power of the combination is
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Always check the focal length unit! If given in cm, use \( P = 100/f \).
\( 100/20 = 5 \text{ D} \).
\( 100/20 = 5 \text{ D} \).
Updated On: Apr 29, 2026
- 9 D
- 6 D
- 5 D
- 10 D
- 11 D
Show Solution
The Correct Option is A
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