Science help?

[rustydog]

In his research paper, student talks about Archimedes' principle and gives, as an example, elevated water sources that deliver water to a municipal area. But I don't see how that's an example of buoyancy. I think it's just gravity that creates the pressure that delivers the water

Comments

[certainthings]

I wish I could help you in these sorts of situations but my brain stopped working several years ago. I just looked up 'buoyancy' in the dictionary to see if there were any definitions that would go with what you mentioned and there wasn't so, perhaps this student is incorrect.

[rustydog]

but my brain stopped working several years ago

Heh, I feel that way too.

Thanks for looking around for me! When I read his paragraph, I thought, "Bzuh? Gravity, yeah?" and then went and read the Wikipedia article on buoyancy to see if Archimedes' principle had other aspects. But the water tower thing still doesn't make sense to me. If the student is wrong, I need to incorporate that in my notes before I return his paper to him. Hmm. I guess I could just say "I'm not sure you're right about this" and leave it at that.

[padawanpooh]

Physics is not my strong suit but I've found some good YT videos that may help? http://www.youtube.com/results?search_query=+buoyancy&aq=f

[rustydog]

Thank you! I watched a video on gravity vs. density, and I already knew everything it was teaching (that was a relief, since the lessons were very basic!) but it did mention gravity. And there's this, from the Wikipedia entry "Water tower": "Water towers are able to supply water even during power outages, because they rely on pressure produced by elevation of water (due to gravity) to push the water into domestic and industrial water distribution systems." That confirms what I thought

[phoenix64]

The concept you're looking for is "hydrostatic pressure". IF MEMORY SERVES, the student sort of has it turned around in that hydrostatic pressure is how water towers work and hydrostatic pressure is also a factor in buoyancy, but buoyancy is not how water towers work. It would be sort of like saying baking is how frying works?

EDIT: Memory does not serve well. Hydrostatic pressure and buoyancy are distinct, just in the same category. But it's definitely hydrostatic pressure behind how the water tower works.