What is the magnifying power of a simple microscope of focal length 5 cm, if the image is formed at the distance of distinct vision ?

Options

A. 4
B. 5
C. 6
D. 7

Explanation

To find the magnifying power of a simple microscope with a focal length of 5 cm, when the image is formed at the distance of distinct vision (which is typically taken as 25 cm), we can use the formula for magnifying power (MP) of a simple microscope:

### Step-by-Step Solution:

1. **Identify the Given Values**:
- Focal length (f) = 5 cm
- Distance of distinct vision (D) = 25 cm

2. **Use the Formula for Magnifying Power**:
The formula for the magnifying power (MP) of a simple microscope is given by:
\[ MP = 1 + \frac{D}{f} \]
where:
- \(D\) is the distance of distinct vision,
- \(f\) is the focal length of the microscope.

3. **Substitute the Values into the Formula**:
Substitute \(D = 25\) cm and \(f = 5\) cm into the formula:
\[ MP = 1 + \frac{25}{5} \]

4. **Calculate the Magnifying Power**:
Now, calculate the fraction:
\[ \frac{25}{5} = 5 \]
Then, add 1 to this result:
\[ MP = 1 + 5 = 6 \]

5. **Final Result**:
Therefore, the magnifying power of the simple microscope is:
\[ MP = 6 \]