MCQ

To increase the angular magnification of a simple microscope, one should increase:

  • A
    The focal length of the lens.
  • B
    The power of the lens.
  • C
    The aperture of the lens.
  • D
    The object size.

Answer

  1. The power of the lens.

Explanation:

For a simple microscope in normal adjustment, the object is placed at a distance equal to f (the ​focal length) from the lens, And the angular magnification is given by the relation

$\text{m}=\frac{\text{D}}{\text{f}}$

for $\text{u}<\text{f},\text{m}=\frac{\text{D}}{\text{f}}+1$

power of lens $=\frac{1}{\text{f}}$

Angular magnification depends on power.

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