In solids interatomic forces are

Options

A. totally repulsive
B. totally attractive
C. Both (a) and (b)
D. None of these

Explanation

To answer the question regarding the nature of interatomic forces in solids, we can break it down step by step.

### Step-by-Step Solution:

1. **Understanding Interatomic Forces**:
Interatomic forces are the forces that act between atoms in a solid. These forces can be classified into two main types: attractive forces and repulsive forces.

2. **Attractive Forces**:
- These forces occur when atoms are at a distance where they can attract each other.
- This attraction is due to the electrostatic forces between positively charged nuclei and negatively charged electrons of adjacent atoms.
- Attractive forces help to hold the atoms together, contributing to the stability of the solid structure.

3. **Repulsive Forces**:
- When atoms come very close to each other, the electron clouds of the atoms begin to repel each other due to the like charges (negatively charged electrons repel each other).
- This repulsion prevents atoms from collapsing into one another and maintains a certain distance between them.

4. **Balance of Forces**:
- In a solid, there is a balance between these attractive and repulsive forces.
- At a certain distance, the attractive forces are strong enough to hold the atoms together, while the repulsive forces prevent them from getting too close.

5. **Conclusion**:
- Therefore, in solids, interatomic forces are both attractive and repulsive.
- This dual nature of forces is essential for the stability and structure of solids.

### Final Answer:
In solids, interatomic forces are both attractive and repulsive.

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