Q31 of 70 Page 11

A compound microscope has an objective of focal length 1.0 cm and an eyepiece of focal length 4.0 cm. If the length of the tube is 20 cm, find the magnification of the compound microscope.

focal length of the object, f0 = 1.0 cm
Eyepiece of focal length, fe = 4.0 cm
Tube–length of the microscope, L = 20 cm
Magnification of compound microscope, m =
                                                            =
                                                            = 5 × 25                                                             = 125Magnification of compound microscope is, m = 125.

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29 How will you distinguish between a compound microscope and a telescope. 30 A lens used as a simple magnifier gives magnification of 6. What is its focal length? 32 A telescope has an objective of focal length 140.0 cm and an eyepiece of focal length 5.0 cm. Find
(i) the magnification of the telescope for viewing distant objects for normal adjustment
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