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If we need a magnification of 400 from c...

If we need a magnification of 400 from compound microscope of tube length 150 mm and an objective of focal length 5 mm, the focal length of the eye-piece, should be dose to : (final Image is at infinity).

A

22mm

B

19mm

C

33mm

D

2mm

Text Solution

Verified by Experts

The correct Answer is:
B
`m=l/(f_(0))D/(f_(e)),fe=(lD)/(f_(0)xxm)=(150xx25)/(5xx400)~~19mm`
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