A screen is placed 90 cm away from an object. The image of the object on the screen is…
Physics · Class 12 · CBSE — Ray Optics & Optical Instruments
A screen is placed 90 cm away from an object. The image of the object on the screen is formed by a convex lens at two different locations separated by 20 cm. Find the focal length of lens.
- 42.8 cm
- 21.4 cm
- 10.7 cm
- 5.5 cm
Answer
(B) 21.4 cm
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