If the aperature of a telescope is decreased resolving power will

Options

A. increases
B. decreases
C. remain same
D. zero

Explanation

To solve the question regarding how the resolving power of a telescope is affected by a decrease in its aperture, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Resolving Power**:
The resolving power of a telescope refers to its ability to distinguish between two closely spaced objects. It is a measure of the detail that can be seen in the images produced by the telescope.

2. **Identify the Formula**:
The resolving power (R) of a telescope is given by the formula:
\[ R = \frac{A}{1.22 \lambda} \]
where:
- \( R \) = resolving power
- \( A \) = aperture of the telescope
- \( \lambda \) = wavelength of light used

3. **Analyze the Relationship**:
From the formula, we can see that the resolving power \( R \) is directly proportional to the aperture \( A \). This means that if the aperture increases, the resolving power increases, and if the aperture decreases, the resolving power decreases.

4. **Consider the Given Condition**:
The question states that the aperture of the telescope is decreased. Therefore, if \( A \) decreases, according to the relationship established, the resolving power \( R \) will also decrease.

5. **Conclusion**:
Since the aperture is decreasing, the resolving power will decrease as well. Thus, the correct answer to the question is that the resolving power will decrease.

### Final Answer:
The resolving power will **decrease** when the aperture of the telescope is decreased.

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