Define resolving power of an optical instrument.

Explanation

### Step-by-Step Solution

1. **Understanding the Concept**: The resolving power of an optical instrument refers to its ability to distinguish between two closely spaced objects. When two objects are very close together, they may appear as a single object to the observer unless the instrument has sufficient resolving power.

2. **Visualizing the Scenario**: Imagine two objects placed near each other. If viewed from a distance without any optical aid, they may merge into one image. However, using an optical instrument (like a microscope or telescope) allows us to see these objects as separate entities.

3. **Defining Resolving Power**: The resolving power is defined as the ability of the optical instrument to separate the images of two objects. If the instrument can display the images of both objects distinctly, it has good resolving power.

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