Assertion (A) To increase resolving power of a telescope, the aperture (a) of the object should be large.
Reason (R ) Resolving power of the telescope is given by `(2a)/(1.22lambda)`.

Options

A. If both Assertion and Reason are true and Reason is correct explanation of Assertion.
B. If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
C. If Assertion is true but Reason is false.
D. If both Assertion and Reason are false.

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Understanding the Assertion
The assertion states that "To increase the resolving power of a telescope, the aperture (a) of the object should be large."

- **Resolving Power**: This is the ability of a telescope to distinguish between two closely spaced objects. A higher resolving power means that the telescope can separate two objects that are very close together.

### Step 2: Understanding the Reason
The reason given is that "Resolving power of the telescope is given by (2a)/(1.22λ)."

- **Formula for Resolving Power**: The resolving power (RP) is indeed related to the aperture of the telescope. The correct formula for resolving power is:
\[ RP = \frac{a}{1.22λ} \]
where \( a \) is the diameter of the aperture and \( λ \) is the wavelength of light being used.

### Step 3: Analyzing the Relationship
From the formula, we can see that resolving power is directly proportional to the aperture size \( a \). Therefore, increasing the aperture will indeed increase the resolving power of the telescope.

### Step 4: Conclusion
- The assertion is **true** because a larger aperture does increase the resolving power of the telescope.
- The reason is **false** because the formula provided in the reason is incorrect; it should be \( \frac{a}{1.22λ} \) instead of \( \frac{2a}{1.22λ} \).

### Final Answer
Thus, the correct conclusion is:
- Assertion (A) is true.
- Reason (R) is false.

The correct option is that the assertion is true, but the reason is false.

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