JEE Mains · Physics · STD 12 - Ray optics and optical instruments
- JEE Mains 2021
- Hard
- Numerical
An object is placed at a distance of \(12 \,{cm}\) from a convex lens. A convex mirror of focal length \(15 \,{cm}\) is placed on other side of lens at \(8 \,{cm}\) as shown in the figure. Image of object coincides with the object.When the convex mirror is removed, a real and inverted image is formed at a position. The distance of the image from the object will be ..... \((cm)\)
Pick an option to check your answer.
Answer & Solution
Correct Answer
(C) \(50\)
Step-by-step Solution
Detailed explanation
For the object to coincide with image, the light must fall perpendicularly to mirror. Which means that the light will have to converge at \({C}\) of mirror.
Without the mirror also, the light would coverage at \({C}\).
Without the mirror also, the light would coverage at \({C}\).
So the distance is : \(12+8+30=50 \,{cm}\)
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