A converging beam of lgiht forms a sharp image on a screen. A lens is placed in the path of the beam, the lens being 10 cm from the screen. It is found that the screen has to be moved 8 cm further away from the lens to obtain as sharp image. Find the focal length and nature of lens.

A converging beam of lgiht forms a sharp image on a screen. A lens is

1.	A converging beam of lgiht forms a sharp image on a screen. A lens is placed in the path of the beam, the lens being 10 cm from the screen. It is found that the screen has to be moved 8 cm further away from the lens to obtain as sharp image. Find the focal length and nature of lens.
Answer» 22.5 CM, convex 22.5 cm, concave 50 cm, convex 50 cm, concave Answer :D

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A converging beam of lgiht forms a sharp image on a screen. A lens is placed in the path of the beam, the lens being 10 cm from the screen. It is found that the screen has to be moved 8 cm further away from the lens to obtain as sharp image. Find the focal length and nature of lens.

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