ice cube floating -> water (more of a brain teaser)

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Mar 23, 2014
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Water is less dense in solid form than in liquid form. So shouldn't the water level decrease?

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It's turning back into the liquid form. When it melts, it will put back the volume of water that was displaced for lifting the solid.
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The ice cube's submerged portion occupies the volume of water that is equal to the weight of the ice. Density is irrelevant. If the ice displaces 2 pounds of water, then the ice weighs 2 pounds, and therefore will not displace less or more than that when it melts. Try this: add some ice to a glass of water and mark the meniscus. Check it after the ice melts and if it's any different, let physicists know because you've just done some incredible voodoo witchcraft.
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