Assertion :- (A) The total number of atoms present in a simple cubic unit cell is one .
Reason :-(R ) Simple cubic cell has atoms at its corners , each of which is shared between eight adjacent unit cells.

Options

A. Assertion and reason both are correct statements and Reason is correct explantion for Assertion .
B. Asserton and Reason both are correct statement but Reason is not correct explanation for assertion .
C. Assertion is correct statement but reason is worng statement .
D. Assertion is Wrong statement but Reason is correct statement .

Explanation

To solve the question regarding the assertion and reason about the simple cubic unit cell, we will break down the problem into clear steps.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that the total number of atoms present in a simple cubic unit cell is 1.
- We need to verify if this statement is true.

2. **Understanding the Simple Cubic Unit Cell**:
- In a simple cubic unit cell, atoms are located at the corners of the cube.
- There are a total of 8 corners in a cube.

3. **Contribution of Atoms at the Corners**:
- Each atom at the corner of the unit cell is shared among 8 adjacent unit cells.
- Therefore, the contribution of each corner atom to the unit cell is \( \frac{1}{8} \).

4. **Calculating the Total Number of Atoms**:
- Since there are 8 corners and each contributes \( \frac{1}{8} \) of an atom, we can calculate the total number of atoms in the unit cell:
\[ \text{Total atoms} = \text{Number of corners} \times \text{Contribution per corner} = 8 \times \frac{1}{8} = 1 \]
- This confirms that the total number of atoms present in a simple cubic unit cell is indeed 1.

5. **Understanding the Reason**:
- The reason states that the simple cubic cell has atoms at its corners, each of which is shared between eight adjacent unit cells.
- This statement is accurate as it correctly describes the arrangement of atoms in a simple cubic unit cell.

6. **Conclusion**:
- Since both the assertion and the reason are correct, and the reason provides a correct explanation for the assertion, we conclude that:
- Assertion (A) is true.
- Reason (R) is true and correctly explains (A).

### Final Answer:
Both the assertion and reason are correct, and the reason is the correct explanation for the assertion.

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