JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
You are asked to design a shaving mirror assuming that a person keeps it \(10\,cm\) from his face and views the magnified image of the face at the closest comfortable distance of \(25\,cm.\) The radius of curvature of the mirror would then be.....\(cm\)
- A \(60\)
- B \(-24\)
- C \(-60\)
- D \(24\)
Answer & Solution
Correct Answer
(C) \(-60\)
Step-by-step Solution
Detailed explanation
convex mirror is used as a shaving mirror. From question \(: v=15\, \mathrm{cm}, u=-10\,\mathrm{cm}\) Radius of curvature, \(R=2\,\,f=?\) Using mirror formula, \(\frac{1}{v}+\frac{1}{u}=\frac{1}{f}\) \(\frac{1}{15}+\frac{1}{(-10)}=\frac{1}{f} \Rightarrow f=-30\, \mathrm{cm}\)…
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