A compound microscope has two lenses. The magnifying power of one is 5 and the combined magnifying power is 100. The magnifying power of the other lens is

Options

A. 10
B. 20
C. 50
D. 25

Answer

To solve the problem, we need to find the magnifying power of the second lens (let's call it \( M_E \)) in a compound microscope, given the magnifying power of the first lens (let's call it \( M_O \)) and the combined magnifying power.

### Step-by-Step Solution:

1. **Identify the Known Values:**
- Magnifying power of the first lens (\( M_O \)) = 5
- Combined magnifying power (\( M \)) = 100

2. **Understand the Relationship:**
- The combined magnifying power of a compound microscope is given by the product of the magnifying powers of the two lenses:
\[ M = M_O \times M_E \]

3. **Substitute the Known Values:**
- We can substitute the known values into the equation:
\[ 100 = 5 \times M_E \]

4. **Solve for \( M_E \):**
- To find \( M_E \), divide both sides of the equation by 5:
\[ M_E = \frac{100}{5} \]
- Calculate \( M_E \):
\[ M_E = 20 \]

5. **Conclusion:**
- The magnifying power of the other lens is \( 20 \).

### Final Answer:
The magnifying power of the other lens is \( 20 \).

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