wherein Liz rambles about vacuum effects and the shape of soda bottles

[edenfalling]

Ways you can tell that I have no life, #26:

I tend to buy a 20 oz plastic bottle of soda when I'm at the computer lab. After I drink the soda, I rinse the bottle and refill it with water, because A) I have a habit of absently eating or drinking while reading or writing, and it's better to drink than eat snacks, B) I hate dehydration headaches, and C) I hate caffeine deprivation headaches even more.

Anyway, I rinse the bottles several times with hot water and then cap them, which means that as they cool, the air inside contracts and creates a vacuum effect, sucking the plastic inward. Physics in action! (The plastic is also rendered slightly more malleable than usual, because it's heated.)

Non-indented/striated bottles, like Dr. Pepper, collapse into triangles. Pepsi bottles, which have lots of closely-set, diagonal indentations at the top and bottom, but a longish smooth section in the middle, collapse into triangles in the smooth section; the top and bottom remain unaffected. Coke bottles, however, collapse into squares or trapezoids. I think the difference is in the spacing of the bottle indentations. Coke bottles have 10 evenly spaced indentations, set roughly 3/4 of an inch apart, which sort of guide the inward collapse of the plastic -- there's a distinct top-and-bottom effect to the collapse, which then creates two parallel sides by default.

I am quite sure this should not fascinate me as much as it does.

Comments

[erised1810.livejournal.com]

if yo uwere ona dutch university this woudln't just be an accepted thesissubject but aslo received enthusiastically, publishe dinaunversity press and be onthe radio inseveral programmes.
this is as geky to me as the caudlro nbottom thickness of Percy Weasley though, lol. i 'msure yif you stil are bored youtake out a measure tape and soem extra bottels and seriously do the rest ofthe research. adn then do another experimentwith different tempretures and with cold water and so forth...

[edenfalling]

I'm not that bored, and anyway, when I do get that bored, I tend to write instead. (Besides, I'm not sure I even have a thermometer in my apartment...)

[erised1810.livejournal.com]

I jstu felt exaclty liek you reacted atthe end. sort of asheepish gri nand 'ok..nowwhat?" anwyay i mainl ysaid it because I have see nwackier research t opics discussed with grad students here. apaprnelty so unimportantthat icna't even remember examles by now.