A liquid can rise to a height of h in a capillary tube of length l `( l gth )`. The tube filled with the liquid is kept horizontal with its two ends open. Now the tube is kept vertical with the liquid in it. Some liquid flows out. Find the height of the liquid remaining in the tube if the surface tension of the liquid is `sigma`.

Explanation

To solve the problem, we need to analyze the situation of a liquid in a capillary tube when it is kept vertical after initially being horizontal. The liquid rises to a height \( h \) due to capillary action, and we need to find the height of the liquid remaining in the tube after some of it flows out.

### Step-by-Step Solution:

1. **Understand the Initial Conditions**:
- The liquid can rise to a height \( h \) in a capillary tube of length \( l \) when it is horizontal.
- The tube is then kept vertical, and some liquid flows out.

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