Assertion (A) : The energy of ultraviolet radiation is greater than the energy of infrared radiation
Reason (R) : The velocity of ultraviolet radiation is greater than the velocity of infrared radiation

Options

A. Both (A) and (R) are true and (R) is the correct explanation of (A)
B. Both (A) and (R) are true and (R) is not the correct explanation of (A)
C. (A) is true but (R) is false
D. (A) is false but (R) is true

Answer

To solve the given question, we will analyze the Assertion (A) and Reason (R) step by step.

### Step 1: Analyze the Assertion (A)
**Assertion (A):** The energy of ultraviolet radiation is greater than the energy of infrared radiation.

- **Explanation:** The energy of electromagnetic radiation is inversely related to its wavelength. This relationship can be expressed as:
\[ E \propto \frac{1}{\lambda} \]
where \(E\) is the energy and \(\lambda\) is the wavelength. Ultraviolet (UV) radiation has a shorter wavelength compared to infrared (IR) radiation. Since the wavelength of UV is less than that of IR, the energy of UV radiation is indeed greater than that of IR radiation.

**Conclusion for Step 1:** The assertion is true.

### Step 2: Analyze the Reason (R)
**Reason (R):** The velocity of ultraviolet radiation is greater than the velocity of infrared radiation.

- **Explanation:** The speed of all electromagnetic radiation in a vacuum is the same, approximately \(3 \times 10^8\) meters per second. This means that both ultraviolet and infrared radiation travel at the same speed in free space. Therefore, the statement that the velocity of ultraviolet radiation is greater than that of infrared radiation is incorrect.

**Conclusion for Step 2:** The reason is false.

### Step 3: Combine the Conclusions
- **Assertion (A)** is true.
- **Reason (R)** is false.

### Final Answer
The correct conclusion is: **A is true, but R is false.**