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CrambleSquash t1_j3qceft wrote

Why not try it?

I would expect so.

Air is a poor heat conductor and so would do a bad job transferring heat into the frozen cube.

Liquid water on the other hand is quite a good conductor of heat.

If heat can efficiently transfer into the water, e.g. from the container the cube is sat in, I would expect this would increase the melting rate.

The water would also provide an additional surface for the heat from the air to flow into.

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bigloser42 t1_j3qqg3u wrote

On one hand I agree with your premise, but you are overlooking the fact that the air will be much warmer than the meltwater. Not sure if the temperature difference would be enough to overcome the difference in thermal conductivity.

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Saidear t1_j3r1kjy wrote

Meltwater is also going to have a higher surface area to absorb latent heat in the air, and is able to more effectively transfer that to the ice cube.

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bigloser42 t1_j3rh6bq wrote

that is purely dependent on the container it sits in. you could easily put ice in a container where the meltwater reduces the surface area

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Game_Minds t1_j3s8rl2 wrote

Yeah there would have to be a range of tests with different container shapes and materials, ice cube size and shape, ice composition and density, ambient temperature and humidity, air flow, water flow, a bunch of stuff would have impacts

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Gogyoo t1_j3rk0dy wrote

I thought that because water has such high specific heat capacity, it would be a good insulator. My instinct muss not be right then...

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VT_Squire t1_j3sgdrh wrote

Think about it this way...

Scenario #1: You jump into water that is 33 degrees

Scenario #2: You walk around outside when it's 33 degrees.

You're wearing nothing but a bathing suit in both scenarios. In which environment are you going to induce hypothermia faster?

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dnkushne t1_j3v0eua wrote

Trick question. In Celsius you get sweaty really fast in both scenarios

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vacri t1_j3tp8mk wrote

Given that body temperature is only 37, there's no hypothermia happening in this situation. Exert yourself and you might get overheated, though.

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kilotesla t1_j3twpjl wrote

I believe that the 33° was supposed to be fahrenheit, for about 0.5° C. Perhaps you knew that and were making a joke, but I'm giving you the benefit of the doubt.

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bisnotyourarmy t1_j3r340k wrote

Air is a poor conductor, but drained ice has higher surface area..... compared to the container of meltwater.

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kilotesla t1_j3txubj wrote

That's possible but not certain. If you had a pile of ice cubes on a grate, such that water could drain away, and warm air could filter through accessing that full surface area, that might result in higher heat transfer than the same ice in a bucket full of melt water where the surface area accessible to the air is the surface of the bucket and the surface of the water, and is smaller than the total surface area of all of the cubes.

But if you froze the ice in the bucket to get a roughly cylindrical block of ice, and put that on the grate with the water draining away, the surface area would start out similar to that of the bucket, but would gradually decrease as the ice melted, whereas if you kept it in the bucket with the melt water, the surface area would stay constant.

Topics left as an exercise for the reader are consideration of heat transfer by radiation and the possibility of putting it in a bucket with a hole in it such that the water drains out. And then the challenge of how to fix a bucket with a hole in it without access to a working bucket, which might be important for getting water necessary to sharpen tools for carrying out the repair operation.

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GiveItStickMan t1_j3uv1pl wrote

I agree with this. Melting ice outside of a bath has 2 functions, drying the thin melted layer and thermal exchange from thermal layer. I thought of this like fins on a heatsink and the melted ice on the exterior as thermal paste.

Also this has variables and would need a test to determine but this was my initial thought also.

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finalattack123 t1_j3qr5a7 wrote

Easy way to try - put a big block of ice in a cup with a little ice water on the bottom half covering the ice cube. My guess is the water half will melt quicker.

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thred_pirate_roberts t1_j3rpc34 wrote

How will you know which half melts faster?

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finalattack123 t1_j3uahgd wrote

The ice cube will melt unevenly. It happens all the time when I poor myself whiskey. Though the whiskey isn’t ice cold. You can easily see the lower half melt faster and become misshapen.

Key element - big chunk of ice

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