The moon undergoes an angular displacement of.......... in 1 day.

Options

A. `30^@`
B. `20^@ 40^@`
C. `15^@ 45`
D. `13^@ 20`

Explanation

To solve the question regarding the angular displacement of the moon in one day, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Angular Displacement**: Angular displacement refers to the angle through which an object has moved in a specified sense about a specified axis. In this case, we are interested in how much the moon moves in one day.

2. **Full Circle Measurement**: A full circle is measured as 360 degrees. This is the total angular displacement for a complete revolution.

3. **Moon's Orbital Period**: The moon takes approximately 27.3 days to complete one full orbit around the Earth. This period is known as the sidereal month.

4. **Calculating Daily Angular Displacement**: To find the angular displacement of the moon in one day, we can divide the total degrees in a circle by the number of days it takes for the moon to complete one orbit:
\[ \text{Angular Displacement per Day} = \frac{360 \text{ degrees}}{27.3 \text{ days}} \approx 13.2 \text{ degrees per day} \]

5. **Conclusion**: Therefore, the moon undergoes an angular displacement of approximately **13.2 degrees** in one day.

### Final Answer:
The moon undergoes an angular displacement of **13.2 degrees** in 1 day.

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