The mirror equation relates u, v and f as
A{'text': '1/v − 1/u = 1/f', 'label': 'A'}
B{'text': '1/u + 1/v = 1/f', 'label': 'B'}
C{'text': 'u v = f', 'label': 'C'}
D{'text': 'u + v = f', 'label': 'D'}
Answer & Solution
Correct answer: B. {'text': '1/u + 1/v = 1/f', 'label': 'B'}
1. NCERT mirror equation: 1/v + 1/u = 1/f.
2. With the sign convention, this works for both concave (f < 0 in Cartesian) and convex mirrors.
3. (B) is the lens formula — a common confusion.
_Source: NCERT Class 12 Physics Part II, Ch 9 §9.2.3_
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