2006-10-20 06:16:32 · 14 answers · asked by Emilee 5 in Science & Mathematics ➔ Mathematics
Have you been smoking those 'funny' cigarettes again?
2006-10-21 08:14:03 · answer #1 · answered by micksmixxx 7 · 0⤊ 0⤋
Approximate relation is weight is proortional to linear dimension cubed.
Imagine your'e a cube. If you double the size of the side ot the cube, its volume increases by a factor of 8 (2cubed=8) Mass=volumex density.
Assume density stays constant, then Mass is proportional to linear dimension cubed (works quite well for animals.. eg Killer whale 8meters long, Blue whale 30 meters long, mass ratio about 50 to one!..ie (30/8)cubed
You are correct, most of this stuff is in 'On Growth and Form'- D'arcy Wentworth Thompson, but some of the stuff on the structure of diatoms is problematic at least and the bit about conformal mappings of the features of hominids is fanciful to say the least!
2006-10-20 22:56:44 · answer #2 · answered by troothskr 4 · 0⤊ 0⤋
They usually aren't. For example a man weighing around 19 stone, for his weight & height to be in proportion he would have to be about 7 foot 3 inches tall.
2006-10-20 13:26:46 · answer #3 · answered by monkeyface 7 · 0⤊ 0⤋
they're in geometric proportion.
If you double the height, you double the lengths of all the bones. That means their cross-sectional area needs to multiply by four to make them as strong. That increases width. Weight would then go up by a factor of eight (cube law), in theory.
In practice there are other forces in the equation and it's not quite that extreme.
Oh yeah and heat generation goes up with weight (factor of eight) but the body surface area goes up more slowly (factor of four), so if you're big, you sweat more cos you can't cool off as well.
D'Arcy Wentworth Thomson explained all of this stuff in "On Growth And Form". This also explains why giant spiders are a physical impossibility.
2006-10-20 13:27:27 · answer #4 · answered by wild_eep 6 · 0⤊ 1⤋
This empirical relation is derived based on statistical data. You can then use regression analysis to set up equation in which it turns out that weight is proportional to height in some range of heights.
2006-10-20 13:20:58 · answer #5 · answered by openpsychy 6 · 1⤊ 0⤋
They are not necessarily in proportion - you can be extremely tall and thin or short and fat. Of you can be tall and fat and small and thin. Obviously a six foot person weighing 10 stone will be a lot thinner than a 5 foot person weighing 10 stone, if that's what you mean. Like having a piece of plasticine and rolling it out.
2006-10-20 13:23:18 · answer #6 · answered by Ally 5 · 0⤊ 0⤋
there is no proportion, one refers to the height of an item, the other refers to the weight
2006-10-20 13:19:01 · answer #7 · answered by The brainteaser 5 · 0⤊ 0⤋
Because the taller you are the bigger your bones, and bones have mass. Therefore, a 6' tall person would have more bone than a 5' tall person and henceforth be "heavier."
Although, there is the fat factor ... and so shorter people can still be heavier than taller people.
2006-10-20 13:18:52 · answer #8 · answered by Leah H 2 · 0⤊ 0⤋
They're not. Unless you're speaking of something very specific. And at the moment, I can't think of anything that is. There should be some though.
2006-10-20 13:18:34 · answer #9 · answered by mmmodem123 3 · 0⤊ 0⤋
Because, if you are tall (about 5'7) and wiegh only 100 pounds than you are probably sick and need therapy. But if you are short (about 4'6) and wiegh 100 pounds, then you are way overwieght and need help.
2006-10-20 13:21:25 · answer #10 · answered by amanda r 2 · 1⤊ 0⤋
Only if the the length, width, and desity are constant.
2006-10-20 13:19:43 · answer #11 · answered by Anonymous · 0⤊ 0⤋