Magnifying power of a microscope depends on

Options

A. colour of light.
B. focal length of objective and colour of light.
C. focal length of eyepiece and colour of light.
D. focal length of eyepiece and objective.

Explanation

To determine what the magnifying power of a microscope depends on, we can analyze the relationship between magnification and the focal lengths of the microscope's components. Here’s a step-by-step solution:

### Step 1: Understand the Components of a Microscope
A microscope typically consists of two main lenses: the objective lens and the eyepiece (ocular lens). Each of these lenses has a specific focal length.

### Step 2: Define Focal Lengths
- Let \( f_o \) be the focal length of the objective lens.
- Let \( f_e \) be the focal length of the eyepiece lens.

### Step 3: Relationship Between Magnification and Focal Lengths
The magnifying power (or magnification) of a microscope can be expressed in terms of these focal lengths. The general formula for magnification \( M \) is given by:

\[ M \propto \frac{1}{f_o \times f_e} \]

This indicates that the magnifying power is inversely proportional to the product of the focal lengths of the objective and the eyepiece.

### Step 4: Conclusion
From the relationship established, we can conclude that the magnifying power of a microscope depends primarily on the focal lengths of the objective and the eyepiece. Therefore, the magnifying power is influenced by:

- The focal length of the objective lens (\( f_o \))
- The focal length of the eyepiece lens (\( f_e \))

Thus, the correct answer is that the magnifying power of a microscope depends on the focal lengths of both the objective and the eyepiece.

### Final Answer
The magnifying power of a microscope depends on the focal lengths of the objective lens and the eyepiece lens.

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