Student Login

Home›Chapters›Ray Optics PYQs›Combination of Lenses›Question 76

JEE Main 2007 (AIEEE) · Combination of Lenses

Combination of Lenses question from JEE Main 2007 (AIEEE)

Q76JEE Main 2007 · AIEEEEasy

Combination of Lenses

Two lenses of power $-15\text{ D}$ and $+5\text{ D}$ are in contact with each other. The focal length of the combination is

Show answer and solution

Answer: (c)

$P = P_1 + P_2 = -15 + 5 = -10\text{ D}$
$f = \frac{1}{P} = -0.1\text{ m} = -10\text{ cm}$
So the answer is (c) $-10\text{ cm}$ .

Report a mistake

More questions on Combination of Lenses

A convex lens and a concave lens, each having same focal length of 25 cm, are put in…NEET 2006 (AIPMT)
A plano convex lens of refractive index 1.5 and radius of curvature 30 cm is silvered at…JEE Main 2004 (AIEEE)
An equiconvex lens is cut into two halves along (i) XOX' and (ii) YOY' as shown in the…NEET 2003 (AIPMT)
For a plano convex lens ( μ = 1.5) has radius of curvature 10 cm. It is silvered on its…NEET 2000 (AIPMT)
A luminous object is placed at a distance of 30 cm from the convex lens of focal length…NEET 1998 (AIPMT)
If a convex lens of focal length 80 cm and a concave lens of focal length 50 cm are…NEET 1996 (AIPMT)
A thin convex lens and a thin concave lens are kept in contact and are co-axial. Which of…JEE Main 2026 (5 Apr, Shift 2)
An equiconvex lens of focal length F is cut in to two equal parts along the vertical…MHT CET 2026 (15 Apr, Shift 1)