JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
A convex lens of focal length \(20\, cm\) produces images of the same magnification \(2\) when an object is kept at two distances \(x_1\) and \(x_2\) \((x_1 > x_2)\) from the lens. The ratio of \(x_1\) and \(x_2\) is
- A \(5 : 3\)
- B \(2 : 1\)
- C \(4 : 3\)
- D \(3 : 1\)
Answer & Solution
Correct Answer
(D) \(3 : 1\)
Step-by-step Solution
Detailed explanation
Magnification is \(2\) If image is real, \(x_{1}=\frac{3 f}{2}\) If image is virtual, \(x_{2}=\frac{f}{2}\) \(\frac{x_{1}}{x_{2}}=3: 1\)
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