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In a compound microscope, the magnified virtual image is formed at a distance of 25 cm from the eye-piece. The focal length of its objective lens is 1 cm . If the magnification is 100 and the tube length of the microscope is 20 cm , then the focal length of the eye-piece lens (in cm ) is ______

Correct answer

0

Step-by-step solution

M = v 0 u 0 1 + D f e M = L f 0 1 + D f e 100 = 20 1 1 + 25 f e ; 5 = 1 + 25 f e 4 = 25 f e ; f e = 25 4 = 6 .25   cm

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