Two thin lenses of focal lengths f₁ and f₂ are in contact and coaxial.

⇦

⇨

Two thin lenses of focal lengths f₁ and f₂ are in contact and coaxial. The power of the combination is:

Options

(a) √ f₁ / f₂
(b) √ f₂ / f₁
(c) f₁ + f₂ / 2
(d) f₁ + f₂ / f₁f₂

Correct Answer:

f₁ + f₂ / f₁f₂

Explanation:

The focal length of the combination
1/f = 1/f₁ + 1/f₂
Power of the combinations,
P = f₁ + f₂ / f₁ f₂ ( P = 1 / f )

Related Questions:

1. A 1m long wire of diameter 0.31 mm has a resistance of 4.2Ω. If it is replaced by
2. A particle of mass 100g tied to a string is rotated along a circle of radius 0.5 m
3. If in a L-R series circuit the power factor is 1/2 and R=100Ω, then the value of L is,
4. The electric field part of an electromagnetic wave in a medium is represented by
5. In a given reaction, ᴢXᴬ → ᴢ+1Yᴬ → ᴢ-1Kᴬ⁻⁴ → ᴢ-1Kᴬ⁻⁴

Topics: Ray Optics (94)
Subject: Physics (2479)

---

Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score

18000+ students are using NEETLab to improve their score. What about you?

Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.

---

Share this page with your friends