What is the shape of the meniscus observed when water and mercury are taken in two different capillary tubes and why ?

Explanation

### Step-by-Step Solution:

1. **Understanding Meniscus**:
- The meniscus is the curved surface of a liquid in a container, such as a capillary tube. It is formed due to the interaction of cohesive and adhesive forces.

2. **Cohesive Forces**:
- These are the forces of attraction between similar molecules. In the case of water, the cohesive forces are strong because water molecules are attracted to each other.

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