COMEDK · Physics · 25. Ray Optics
A lens of power \(+1 \mathrm{D}\) is made in contact with another lens of power \(-2 \mathrm{D}\) the combination will then act as a:
- A converging lens of focal length \(33.3 \mathrm{~cm}\)
- B diverging lens of focal length \(33.3 \mathrm{~cm}\)
- C diverging lens of focal length \(100 \mathrm{~cm}\)
- D Converging lens of focal length \(100 \mathrm{~cm}\)
Answer & Solution
Correct Answer
(C) diverging lens of focal length \(100 \mathrm{~cm}\)
Step-by-step Solution
Detailed explanation
The power of a combination of thin lenses in contact is given by the algebraic sum of the individual powers of the lenses: \(P = P_1 + P_2\). Given \(P_1 = +1 \mathrm{D}\) and \(P_2 = -2 \mathrm{D}\), the effective power \(P\) is:…
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