it is not concerned about melting of ice since level remains same even after melting of ice but level of water falls due to the glass ball in the ice block. glass is much denser than water so it sinks thereby displacing the volume of water equal to its own wall which is much lesser than that when it was in ice. therefore water falls

Explanation:

When an ice block containing a glass ball melts within a water-containing vessel, the level of water in the vessel will fall. This can be explained by considering the properties of ice and water.

Expansion:

1. Density of Ice:
Ice is less dense than water. When water freezes and turns into ice, its molecules form a regular lattice structure, which causes the ice to be less dense than the liquid water. As a result, ice floats on water.

2. Volume of Ice and Water:
When ice melts, it transforms from a solid state to a liquid state. The molecules in the ice gain energy and start moving more freely, causing the ice to melt into water. The volume of water formed by the melted ice is equal to the volume of the ice itself.

3. Archimedes' Principle:
Archimedes' principle states that an object immersed in a fluid experiences an upward buoyant force equal to the weight of the fluid it displaces. When the ice block is immersed in the water-containing vessel, it displaces a certain volume of water equal to its own volume.

4. Effect on Water Level:
As the ice block melts, it transforms into water, which already exists in the vessel. Since the volume of water formed by the melted ice is equal to the volume of the ice, the total volume of water in the vessel remains unchanged. However, the ice block initially displaced its own volume of water due to Archimedes' principle.

Conclusion:
As a result, when the ice melts, the water level in the vessel will fall. This is because the volume of water formed by the melted ice is less than the volume of water that was initially displaced by the ice block. Therefore, the water level decreases as the ice block melts.