JEE Advanced · 2007 · 08 Apr 2007 · Paper 1 · Geometrical Optics

STATEMENT-1
The formula connecting

u, v

and

f

for a spherical mirror is valid only for mirrors whose sizes are very small compared to their radii of curvature.
because
STATEMENT-2
Laws of reflection are strictly valid for plane surfaces, but not for large spherical surfaces.

(A)Statement-1 is True, Statement-2 is True; Statement-2 is a correct explanation for Statement-1
(B)Statement-1 is True, Statement-2 is True; Statement-2 is NOT a correct explanation for Statement-1
(C)Statement-1 is True, Statement-2 is False✓ Correct
(D)Statement-1 is False, Statement-2 is True

Answer: (C)

Solution

Statement-1: The mirror formula

\frac{1}{f} = \frac{1}{u} + \frac{1}{v}

is derived under the paraxial approximation, which assumes that rays make small angles with the principal axis. This is valid when the mirror's aperture is small compared to its radius of curvature. Statement-1 is True.

Statement-2: The laws of reflection (angle of incidence equals angle of reflection) are universally valid for all surfaces, including large spherical surfaces. They are fundamental laws of optics. Statement-2 is False.

Therefore, the answer is (C).

JEE Advanced · 2007 · 08 Apr 2007 · Paper 1 · Single correct option

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JEE Advanced · 2007 · 08 Apr 2007 · Paper 1 · Geometrical Optics

Solution

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