A glass capillary tube of internal radius `r=0.25 mm` is immersed in water. The top end of the tube projects by `2 cm` above the surface of water. At what angle does the liquid meet the tube? Surface tension of water `=0.7Nm^(-1)`.

Explanation

To solve the problem of finding the angle at which the liquid meets the capillary tube, we can follow these steps:

### Step 1: Understand the forces acting on the liquid in the capillary tube
The liquid in the capillary tube experiences two main forces:
1. The upward force due to surface tension.
2. The downward force due to the weight of the liquid column.

### Step 2: Write the expression for the force due to surface tension
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