What make it difficult to separate two glass sheets having a drop of water between them .

Options

A. Viscosity
B. Gravity
C. Surface tension
D. Atmospheric pressure

Answer

To understand why it is difficult to separate two glass sheets with a drop of water between them, we can break down the explanation into a series of logical steps:

### Step-by-Step Solution:

1. **Understanding the Setup**:
- We have two glass sheets placed parallel to each other with a drop of water in between.

2. **Cohesive Forces**:
- Water molecules exhibit cohesive forces, which are the attractive forces between like molecules. This means that the water molecules are attracted to each other.

3. **Adhesive Forces**:
- Water molecules also exhibit adhesive forces, which are the attractive forces between different substances. In this case, the water molecules are attracted to the glass surfaces.

4. **Interaction of Forces**:
- When the drop of water is placed between the two glass sheets, the water molecules adhere to the glass surfaces (adhesive forces) and also attract each other (cohesive forces).

5. **Resulting Effect**:
- When you try to separate the two glass sheets, the adhesive forces between the water and the glass sheets, combined with the cohesive forces among the water molecules, create a strong bond. This bond acts like glue, making it difficult to pull the sheets apart.

6. **Role of Surface Tension**:
- The phenomenon described is related to surface tension, which is the result of cohesive forces in the liquid. Surface tension causes the water to behave as if it has a "skin," further contributing to the difficulty in separating the sheets.

7. **Conclusion**:
- Therefore, the difficulty in separating the two glass sheets is primarily due to the combined effects of cohesive and adhesive forces, which are manifestations of surface tension.