Physics-
General
Easy
Question
A convex lens forms an image of an object on a screen. The height of the image is 9 cm. The lens is now displaced until an image is again obtained on the screen. The height of this image is 4 cm. The distance between the object and the screen is 90 cm.
- The focal length of the lens is 21.6 cm.
- The distance of the object from the lens in its first position is 36 cm.
- The height of the abject is 6 cm.
- All of the above
The correct answer is: All of the above
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