A compound microscope is of magnifying power 100". The magnifying power of its eyepiece is 4. Find the magnification of its objective

Options

A. 25
B. 20
C. 15
D. 30

Answer

To find the magnification of the objective in a compound microscope, we can use the relationship between the total magnification of the microscope, the magnification of the eyepiece, and the magnification of the objective.

### Step-by-Step Solution:

1. **Understand the given information:**
- Total magnifying power of the compound microscope (M) = 100
- Magnifying power of the eyepiece (Me) = 4

2. **Use the formula for total magnification:**
The total magnification (M) of a compound microscope is given by the product of the magnification of the eyepiece (Me) and the magnification of the objective (Mo):
\[ M = Me \times Mo \]

3. **Substitute the known values into the formula:**
\[ 100 = 4 \times Mo \]

4. **Solve for the magnification of the objective (Mo):**
To find Mo, divide both sides of the equation by 4:
\[ Mo = \frac{100}{4} \]

5. **Calculate the result:**
\[ Mo = 25 \]

### Final Answer:
The magnification of the objective is **25**.

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