what will happen if i close a basin's lid and fill it with water and then then open it ? in which way and how will the water go down ?

When you close a basin's lid and fill it with water, the water will stay in the basin as long as the lid is closed. This is because the lid creates a barrier that prevents the water from escaping.

When you open the lid, the water will start to go down the drain. The direction and speed at which the water goes down will depend on a few factors:

1. The design of the basin: Some basins are designed to drain water quickly, while others are designed to drain water slowly. This can affect the direction and speed at which the water goes down.

2. The amount of water in the basin: If the basin is full of water, the water will go down the drain faster than if the basin is only half full. This is because the pressure of the water in the basin pushes the water down the drain.

3. The size of the drain: A larger drain will allow the water to go down faster than a smaller drain. This is because a larger drain has a larger area for the water to flow through.

4. The angle of the basin: If the basin is tilted, the water will go down the drain in the direction of the tilt. If the basin is level, the water will go down the drain evenly.

In general, when you open the lid of a basin filled with water, the water will go down the drain in the direction of the drain and at a speed determined by the factors listed above.