A convex lens from a real image 16 cm long on a screen. Without altering the position of the object and screen, the lens is displaced so as to again get a real image 4 cm long on screen. What is size of the object ?

A convex lens from a real image 16 cm long on a screen. Without alteri

1.	A convex lens from a real image 16 cm long on a screen. Without altering the position of the object and screen, the lens is displaced so as to again get a real image 4 cm long on screen. What is size of the object ?
Answer» 8 CM 6 cm 4 cm 2 cm Solution :(a) Size of object, `O = sqrt(I_(1). I_(2) = sqrt(16 XX 4) = 8 cm`.

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A convex lens from a real image 16 cm long on a screen. Without altering the position of the object and screen, the lens is displaced so as to again get a real image 4 cm long on screen. What is size of the object ?

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