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Old 02-03-2013, 06:46 PM   #301936
mkodama
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Quote:
Originally Posted by dmax View Post
I remember when I studied Thermodynamics in college that if you ate a 1,000 calorie meal (food calories are really 1,000 'real' calories) and you wanted to neutralize the effect, all you had to do was eat 17 lbs. of ice.

I remember thinking, man, our body is really good at producing energy from food.

Someone can doublecheck my math...it was a while ago, but I'm sure I'm remembering correctly.

Eat whatever you want, and then a ton of ice afterwards!
17 pounds = 7.7 kg.

heat of fusion/melting for ice is 334 kJ/kg so that would mean 2572 kJ to just melt 0C ice and turn it to 0C water.

2572kJ equates to 614 large calories.

warming up the water to body temp:

7.7 kg * 4.186 kJ/kgK * 37 K = 1193 kJ = 285 large calories

614+285 = 899 large calories to melt 17 pounds of ice.

Not far off.
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