today's physics brain teaser

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Dec 9, 2005 | 05:31 PM

#16

78f-150Supercab

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From: San Antonio, TX

Quote:

Originally Posted by pchristman

Similar question. A glass of water, containing a large ice cube, is filled to the brim, such that one more drop will make it overflow. Like an iceberg, most of the ice is beneath the surface, but part of it is above. When the ice melts, what will happen to to the water level?

I would first think that it would overflow because when the ice melts, the portion above the surface of the water would move the water level up.

But then you have to remember that water expands when it is frozen. When the cube melts, it takes up less room and wouldn't cause the glass to overflow.

Dec 9, 2005 | 09:46 PM

#17

pfogle

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From: Oak Harbor, OH

that depends on the size of the cube.

Dec 10, 2005 | 02:08 AM

#18

78f-150Supercab

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From: San Antonio, TX

Quote:

Originally Posted by pfogle

that depends on the size of the cube.

And the size of the glass ;-)

Dec 10, 2005 | 04:13 AM

#19

furball69

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From: Calgary, Canada

I tried that with a rye and coke and an ice cube; the level of the rye and coke steadily decreased.

Dec 10, 2005 | 11:30 AM

#20

pchristman

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From: KCMO

Quote:

Originally Posted by pfogle

that depends on the size of the cube.

Does it? The amount of water in the ice cube will weigh the same, liquid or solid. Only the volume changes with temperature. Objects that float displace their weight, while objects that don't float displace their volume.