The time interval between two successive noon when sun passes through zenith point ( meridian ) is known as

Options

A. 1. sidereal day
B. 2. mean solar day
C. 3. solar year
D. 4. lunar month

Explanation

To solve the question, we need to identify what the time interval between two successive noons is called when the sun passes through the zenith point (meridian).

### Step-by-Step Solution:

1. **Understanding the Concept of Noon**:
- Noon is defined as the time when the sun is at its highest point in the sky, which is also referred to as the zenith point or meridian point.

2. **Earth's Rotation**:
- The Earth rotates on its axis, completing one full rotation approximately every 24 hours. This rotation causes the sun to appear to move across the sky.

3. **Identifying Successive Noons**:
- When we say "successive noons," we are referring to the time interval between two instances when the sun is at its zenith point for a specific location on Earth.

4. **Time Interval Calculation**:
- Since the Earth rotates once every 24 hours, the time interval between two successive noons (when the sun is directly overhead at the same location) is 24 hours.

5. **Conclusion**:
- Therefore, the time interval between two successive noons when the sun passes through the zenith point is known as the **Mean Solar Day**.

### Final Answer:
The time interval between two successive noons when the sun passes through the zenith point (meridian) is known as the **Mean Solar Day**.

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