Measuring the Volume of My Body
Date: 09/17/2003 at 11:42:54 From: Adelfa Subject: Density of human What is the most efficient way of calculating the density of a human being? If actual experiment is not possible, what would be different conversions I have to do to get my volume? I have considered doing the displacement where I will use the bath tub as the container. Then submerged myself in it. The problem is I cannot do this alone. Who will measure the level of water after I go into the tub? So, I am looking for another means of calculating my density.
Date: 09/17/2003 at 14:45:52 From: Doctor Rick Subject: Re: Density of human Hi, Adelfa. If you float but just barely, as most of us do, then we know already that your density is slightly less than that of water, 1 gram/cm^3. How precise do you want to be? I don't think that we could calculate your volume from measurements precisely enough even to predict accurately whether you would float or sink. We are left with something akin to the displacement method that you are rejecting. I'm thinking about a related method that does not require measurement of the displaced volume of water. Assuming you do float, you could completely submerge yourself in a swimming pool, taking a bunch of weights with you, enough to hold you down. Drop the weights one at a time until you have neutral buoyancy (just barely starting to drift upward). The combined mass of your body and the weights you are still holding is equal to the mass of displaced water, that is, the density of water times the total volume of your body and the weights. From this, knowing the mass and density of the weights, along with your own mass, you can determine your volume. - Doctor Rick, The Math Forum http://mathforum.org/dr.math/
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