Quote:
Originally posted by stevie667
Originally posted by stevie667
btw, it's energy not matter that can't be created or destroyed, only moved from one state to another.
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Mass is conserved (with the exception of nuclear reactions). Momentum and energy are also conserved.
http://www.mathpages.com/home/kmath407/kmath407.htm
Quote:
Originally posted by Shpoop
but not in terms of food lbs, in terms of real weight, if u weigh one pound of donuts would u really gain 5 pounds?
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When you start talking about how much you gain from eating something, you have to account for the time it takes you to digest the food, the energy supplied to the body from the air you breath during that time period, anything else you ingest during that time period, the urine and feces that you expel during that time period, and the energy your body consumes during that time period. You're adding in a lot of factors, many of which are difficult to quantify.
The "experiment" that is being referred to is simple. He drinks the water and weighs himself immediately afterwards. From the time he drinks the water to the time that he weighs himself, all he has done is take a few breaths. The mass of the air taken in is negligible since air weighs about 1.2 g/L at standard temperature and pressure and your lungs can only take in a couple liters of air.
To make a long story short, your mass should change by exactly the mass of the water you drank if you wieghed yourself right after you drank the water. The difference in weights is an error.