JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
An object is placed at the focus of concave lens having focal length \(f\). What is the magnification and distance of the image from the optical centre of the lens?
- A \(1, \infty\)
- B Very high, \(\infty\)
- C \(\frac{1}{2}, \frac{f}{2}\)
- D \(\frac{1}{4}, \frac{f}{4}\)
Answer & Solution
Correct Answer
(C) \(\frac{1}{2}, \frac{f}{2}\)
Step-by-step Solution
Detailed explanation
\({U}=-{f}\) \(\frac{1}{{V}}-\frac{1}{{U}}=\frac{1}{-{f}} \Rightarrow \frac{1}{{V}}=-\frac{2}{{f}}\) \({V}=\frac{-{f}}{2}\) \({m}=\frac{{V}}{{U}}=\frac{1}{2}\) distance \(=\frac{{f}}{2}\)
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