If I wanted to make a pair of shoes out of cork so I could walk on water, how big would they need to be?

Question

Say I weigh 200 pounds.

Answer 1

It would be the shape and how they displace water.

Answer 2

If u plan on walking with cork shoes it wud have to be in the form of a boat so that it cud cut thru water...and more over u shud have a grip at ur thumb so that u can have a hold. and the shoe size will be a approximately ur feetsize + extra half size of ur feet which means ur total shoe size will be 1&1/2 per feet or even twice the size of ur foot so that u get a proper balance as the material is light and has a good buoyancy and all that wud happen wud be u toppling all over the water like a floater lol. So as per my idea u will have to have all these aspects while making the shoe. Ofcourse the cork will have to be thick enuf to sustain ur 200 pounds.

Answer 3

Assume the cork is massless (close enough for purposes of your question). You want enough volume to displace 200 pounds.

So that's 200 pints, or 25 gallons. Each shoe should be at least half that. Maybe a bit bigger since the cork weighs something. And spread it out enough so that it's not tippy. So in effect, you end up with two little boats on your feet. I don't think Jesus would have looked stylish in those.

Answer 4

This is actually an easy problem. Your pair of shoes would need to displace 200 pounds,, plus the weight of the shoes, of water. Call that weight buoyancy B = rho g V = W (your weight) + w (the weight of the shoes). So V = (W + w)/rho g; where rho is the mass density of water (in slugs/ft^3) and g = 32.2 ft/sec^2.

Assuming your two shoes are the same size, then the volume of each shoe must be v = V/2 ft^3 for you to float. Look up rho, the mass density of water, and you can work the problem yourself.

There is a center of gravity issue however. Make the shoes wide and long enough that your center of gravity (CG) remains inside the shoe dimensions as you walk. If CG were to fall ouside the base of your shoes, you'd topple over and, probably, drown hanging upside down in the water while the shoes floated on top. Not an ideal result.

The physics is this. When your weight including the shoes = w + W = B = rho g V; you will float because the buoyancy pushing up exactly offsets your weight pulling down, and you will not sink any further.

Answer 5

Yeah shape makes more difference so you're not hanging upside down by your feet. I saw a guy on tv make something you sit on that was disc shaped and had a ring of air around the rim. Perhaps if you made a ring of cork around your feet so your weight could sink through the center some it would help stabilize you. Make sure you can bail easily though in case you do fall in the water.

Answer 6

You got a few pretty good answers for standing on water, but one seems to have ignored the mass of the cork itself, though the rounding of 200lb to 100kg probably compensated for that.

But you said "walk", so here we need to define "walk" if you'll settle for shuffling your feet (perhaps with hinged paddles on the floats to get some "traction") the previous answers will work, but if you want to pick up your feet like walking on a solid floor you'll have to double the volume and put half of that on each foot. (good luck not falling over, maybe two nesting "U" shaped floats might help)

Answer 7

based on Mrs.Bekki’s highly reliable calculations I can conclude that as soon as you are launched you’ll loose your equilibrium immediately and be drowned upside down with cork shoes indicating the place of my late buddy Jack. Gosh what a loss! I hope the stock of champagne bottles with corks in Utah is not sufficient to implement your project!

Answer 8

You could design the right shape and size shoe to make the combined density less than that of water. But that's not hte problem. The problem is stability. Once your center of gravity is higher than the center of buoyancy, you'll topple over. In other words, you'll roll on water. Try placing an empty bottle vertically in the water and see what happens. It floats, but on its side only.

Answer 9

you weight 200 pound about 100Kg right actually its 90 but lets takee 100 .

density of water 1000Kgm^-3

Upthrust needed =100(10)=1000N

P=10X1000X0.1
1000Pa

Ok take any shape but make the area you are standing on 1m^2 and thickness 0.1m =10 cm


tell me did it work or not

Answer 10

as long as your shadow will not fall out of the cork that size will be enough. But it must be4 inch thick.