Today I Heard My First . . . . .
ChatterBank2 mins ago
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The level remains constant.
By Archimedes' Principle, the upthrust equals the weight of water displaced. The weight of the ice cubes = weight of the water displaced which is the volume of water below the water line. When the ice melts it will have a volume that fits into the space occupied by the ice that was underwater.
Hammer: But if ice is less dense than water, when it melts it would have a smaller volume, so the level in the glass would go down, wouldn't it?
The level of ice would go down, but as the ice melts, the ice would shrink down to the level where the water is in the first place. In other words, the total volume of the ice below and above the water level will be replaced by a volume of water equal to the volume of the ice below the water level only. In other words, the water will stay at the same level.
rojash: The density of ice at 0 degrees Celsius is less than the density of water at 0 degrees Celsius, ie ice has more volume than water.