An upright object is placed at a distance of 40 cm in front of a convergent lens of focal length 20 cm. A convergent mirror of focal length 10 cm is placed at a distance of 60 cm on the other side of the lens. The position and size of the final image will be:
- (A)40 cm from the convergent mirror, same size as the object
- (B)20 cm from the convergent mirror, same size as the object
- (C)40 cm from the convergent lens, twice the size of the object
- (D)20 cm from the convergent mirror, twice the size of the object
Solution
Lens (): cm, . This image lies cm in front of the mirror. Mirror (): cm, ; the image is cm from the lens. Light now returns through the lens (): cm, . Net magnification , so the final image is cm from the lens (object side), same size, inverted. No option gives ' cm from the lens, same size', so the question is a bonus.
JEE Main · 2019 · 08 Apr 2019 · Shift 1 · Single correct option