JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
Distance between object and its image \(\left( \text{magnified by } -\frac{1}{3}\right)\) is 30 cm. The focal length of the mirror used is \(\left(\frac{x}{4}\right) \mathrm{cm}\),
where magnitude of value of \(x\) is _________.
- A 40
- B 45
- C 50
- D 55
Answer & Solution
Correct Answer
(B) 45
Step-by-step Solution
Detailed explanation
\(\begin{aligned} & M=-\frac{1}{3} \\ & -\frac{-V}{-U}=\frac{-1}{3} \Rightarrow V=\frac{U}{3}\end{aligned}\) Distance \(b / w\) object and image :…
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