Shape of menuscus of a liquid of zero angle of contact is

Answer

To determine the shape of the meniscus of a liquid with a zero angle of contact, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Meniscus Formation**:
- When a liquid is placed in a capillary tube, it either rises or falls depending on its adhesive and cohesive forces. This results in the formation of a meniscus, which is the curved surface of the liquid.

2. **Defining Angle of Contact**:
- The angle of contact (or wetting angle) is defined as the angle between the tangent to the liquid surface at the point of contact and the solid surface of the tube.

3. **Identifying Zero Angle of Contact**:
- A zero angle of contact means that the tangent to the meniscus at the point of contact with the tube is parallel to the wall of the tube. This indicates that there is no tendency for the liquid to either rise or fall in the tube.

4. **Shape of the Meniscus**:
- For a liquid to have a zero angle of contact, the meniscus must be shaped such that it does not curve upwards or downwards. The only shape that satisfies this condition is a flat or cylindrical shape.

5. **Conclusion**:
- Therefore, the shape of the meniscus of a liquid with a zero angle of contact is cylindrical.

### Final Answer:
The shape of the meniscus of a liquid with a zero angle of contact is cylindrical.

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