What is your volume and density? Physics Project Archimedes Principle?

Question

I am taking a college level physics class and we were giving a project and I am very lost, could someone please help me? Best answer will be chosen!
Stats: I'm 35 years old, this is my first physics class and it just seems very confusing.

The project is:

What is your volume and density? Using principles such as archimedes, or pascals, (etc) whatever applies. You must calculate your volume and denisty or a kids. Volume in cubic meters. MAY NOT TAKE MEASUREMENTS OF YOUR BODY. Must use principles learned. Once you have calculated your volume, then calculate density in kilograms per cubic meter. Next, explain procedure used to come up with volume and density and principles used-state it. Then compare your denisty to density of water for fresh and saltwater and discuss the physical ramifications of your results (think about swimming/and does your answer make sense.

Thanks!!!!!!

Answer 1

Use Archimedes's principle to find your volume, by immersing yourself in a large container of water (bathtub) and marking the water level. (A piece of adhesive tape may be useful if you don't want to leave a mark on the tub.) You may need help in making the mark when you are totally immersed, and you may need to hold weights, or get help, to stay completely immersed. You will sink more easily in fresh water than salt water, and with lungs emptied. Then get out of the tub and measure the water you must add to bring the level back up to the mark. (You don't need to precalibrate the tub with liter marks, and you don't have to know its dimensions to do this.) That's your volume. Subtract any additional volume taken up by weights or the hands and wrists of someone holding you under. (You can measure these separately in a smaller container, again using Archimedes's displacement principle.) In reporting the experiment, note whether you filled your lungs to capacity or emptied them fully. One or the other is better than partly full since the full or empty condition is better defined and reproducible.
You can figure your density as your mass (weight / gravitational acceleration; e.g. mass in kg = weight in Newtons / 9.80665 m/sec^2) divided by your volume. Since the question asks for density in kg/m^3, remember that you must divide volume in liters by 1000 for volume in m^3. The answer with lungs emptied should not be very far from the average value of 945 kg/m^3 (per the reference). If you carry a high proportion of fat it will be less; if a low proportion, more.
As catarthur noted, you do have to know your weight. (And this should be determined at about the same time you do the displacement measurement because your weight can vary quite a bit over the course of a day.) If you naturally float in water, you can find your weight from the weight of water you displace when floating, which is the displaced volume, measured the same way as your immersed volume, times the density of the water you use. (The density of fresh water is 998 kg/m^3 at 20C; if you are using salt water you will need to determine its density by weighing a known volume of it.) But if you naturally sink, you'd have to measure your weight either directly (out of water) or indirectly. In the indirect method you measure your sunken weight, which of course is much less than your true weight; then add the weight of the displaced water, which is determined as in the naturally-floating case. So if you naturally sink, you may not be able to satisfy the no-measurement rule. But the whole point of this exercise is finding density by measuring your displaced volume, and that's essentially a measurement of your body. I think the rule was badly expressed, and its actual intent was to discourage trying to deduce volume from size measurements of your body.

Answer 2

To get your volume, you will need a tub with straight sides.

Fill it enough so that you can completely immerse yourself into it and mesaure how high the water rises. That shows how much you displace the water.

Now, let's say the tub is 2 meter by 1 meter and you raise the water level by .25 meters (these figures are probably not even close), then your volume would be 2 * 1 * .25 or .5 cubic meters.

Get your weight (to make it easy I am going to assume that you weigh 100KG) and divde that by your volume or 100/.5 which gives you 200 kg/cubic meter.

You can then get the density of the other substances (check your physics books or do a search on the web) and finish your project.

Answer 3

The solution is to submerge yourself in water and take measurement of the increase in water volume. The increase is your body volume.
Try drawing a scale on the bath tub this way:
Step1 - take 1 liter which is 1 cubic decimeter of water with a Coca-Cola bottle and pour it into the bath tub
Step 2 - mark the water level somehow on the bath tub with one
Repeat this 2 steps marking every liter increase until the bath tub is full.
Then you leave enough water inside so you can completely submerge yourself in it and the measure the increase and you have your volume in liters.

If you don't want to scratch your bath tub trying to draw a scale, you can use a big rectangular aquarium and do the same submerging.

Volume = width x length x height

Since you can easily measure the width and the length, after submerging in water, you have the height and you'll be able to calculate it :

Your volume = Aquarium width x Aquarium length x Level difference

Be sure to use the same unit measure and make the correct transformations.

1 meter = 10 decimeters = 100 centimeters
1 cubic meter = 1000 decimeters = 1000 liters

For your density simply divide your weight to your volume.
Good luck

Answer 4

Using archimedes, you can submerge yourself in a tub of water, and measure the amount by which the water level rises, and then (after calculating how much water your tub holds) you can calculate your volume. You can do this is fresh water or saltwater although saltwater would be hard..

Density is your VOLUME divided by YOUR MASS (kilograms)..

Look up archimedes for more ideas. What an interesting project! Good luck! :)

Answer 5

For me it is very easy. My density is close to 1.0. I know because if I go in a pool and take a small breath, I sink to the bottom but with a big breath, I float. So my density revolves around 1.0. If you don't sink, you can add some lead weight (volume is negligible) and see how much you need to just barely sink. You would get you volume from the equation

1.0 = (W + L)/V where
W is your weight in kg
V your volume in liters
L is the lead weight in kg

then your density would be d = W/V

Myself knowing my weight is 90kg, my volume is 90 liters. But of course I had to take one measurement: my weight. I really don't know how you could achieve this project without taking a single measurement of your body...

Hope this helps.

Answer 6

You need to design it such that it displaces more than 11.3 x it's own mass, of water. I think the best design would be square or rectangular, but flat bottomed. A square would have the best base area for compactness, but a rectangular "barge" would be more boat- like.