Question
  1. Draw a neat labelled ray diagram of a compound microscope. Explain briefly its working.
  2. Why must both the objective and the eye-piece of a compound microscope have short focal lengths?

Answer


The objective forms a real, inverted, magnified image of the object. This serves as the object for the second lens, the eyepiece, which functions essentially like a simple microscope or magnifier, produces the final image, which is enlarged and virtual.
To achieve a large magnification of a small object; both the objective and eyepiece should have small focal lengths.

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