JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
A concave mirror for face viewing has focal length of \(0.4\,m.\) The distance at which you hold the mirror from your face in order to see your image upright with a magnification of \(5\) is......\(m\)
- A \(0.16\)
- B \(1.60\)
- C \(0.24\)
- D \(0.32\)
Answer & Solution
Correct Answer
(D) \(0.32\)
Step-by-step Solution
Detailed explanation
\(m = \frac{f}{{f - u}}\) \(5 = \frac{{ - 40}}{{ - 40 - u}}\,;\,u\, = \, - 32\,cm\)
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