JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
A convex mirror of radius of curvature \(30 \mathrm{~cm}\) forms an image that is half the size of the object. The object distance is :
- A \(-15 \mathrm{~cm}\)
- B \(45 \mathrm{~cm}\)
- C \(-45 \mathrm{~cm}\)
- D \(15 \mathrm{~cm}\)
Answer & Solution
Correct Answer
(A) \(-15 \mathrm{~cm}\)
Step-by-step Solution
Detailed explanation
\( \text { Given } R=30 \mathrm{~cm} \) \( \mathrm{f}=\mathrm{R} / 2=+15 \mathrm{~cm}\) Magnification \((\mathrm{m})= \pm \frac{1}{2}\) For convex mirror, virtual image is formed for real object. Therefore, \(\mathrm{m}\) is +ve \( \frac{1}{2}=\frac{f}{f-u} \)…
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