Assertion : Sound would travel faster on a not summer day than on a cold winter day,
Reason : Velocity of sound is directly proportional to the square root of its aboslute temperature.

Options

A. If both the Asseration and Reason are true and reason explains the Assertion :
B. If both the Assertion and Reason are true but reason does ot explain the Assertion :
C. If Assertion is true but reason false
D. If Assertion is false but reason is true

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 "Sound would travel faster on a hot summer day than on a cold winter day."

**Explanation**:
- The speed of sound in air is affected by temperature. As the temperature increases, the molecules in the air move faster, which allows sound waves to propagate more quickly. Conversely, on a cold winter day, the temperature is lower, and the molecules move slower, resulting in a slower speed of sound.

### Step 2: Analyzing the Reason
The reason states that "Velocity of sound is directly proportional to the square root of its absolute temperature."

**Explanation**:
- The formula for the speed of sound in a gas is given by:
\[ v = \sqrt{\frac{\gamma R T}{M}} \]
where \( v \) is the velocity of sound, \( \gamma \) is the adiabatic index (constant for a given gas), \( R \) is the universal gas constant (also constant), \( T \) is the absolute temperature, and \( M \) is the molar mass (constant for a specific gas).
- From this formula, we can see that the velocity of sound is indeed proportional to the square root of the absolute temperature \( T \).

### Step 3: Conclusion
Since both the assertion and the reason are correct, and the reason correctly explains the assertion, we conclude that:

- **Assertion**: True
- **Reason**: True
- **Relationship**: The reason explains the assertion.

### Final Answer
Both assertion and reason are true, and the reason explains the assertion.

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