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# Case study question on Compound microscope

Compound microscope-

A compound microscope is an optical instrument used for observing high magnified image of tiny objects. Magnifying power of compound microscope is defined as the ratio of the angle subtended at the eye by the final image to the angle subtended by the object , when both the final image and object at the least distance of distinct vision from the eye . It can be given that:m=mexm0, where me is the magnifying power of eyepiece and m0 is the magnifying power of objective lens. Suppose a lens of focal length 2.0cm and another of 6.25 cm separated by distance 15 cm .

(i) The object distance of eye piece , so that final image is formed at the least distance of distinct vision will be (a) 3.45cm  (b)5cm (c)1.29cm (d) 2.59cm.

(ii)How far from the objective should an object be placed in order to obtain the condition given in (i). (a)4.5cm (b)2.5cm (c) 1.5cm (d) 3.0cm .

(iii) What  is the magnifying power of the microscope in case of list distinct of vision? (a)20 (b)30 (c)40 (d)10 .

(iv) The intermediate image formed by the objective of a compound microscope is (a) real, inverted and magnified (b) real erect and magnified (c) virtual , erect and magnified (d) virtual, inverted and magnified .

(v) The magnifying power of compound microscope is increases with .(a) f0 increases and fe decreased (b)fe increased and f0 decreased (c) both increased (d) both decreased .