{"id":14674,"date":"2013-09-29T10:10:49","date_gmt":"2013-09-29T14:10:49","guid":{"rendered":"http:\/\/www.kith.org\/journals\/vardibidian\/2013\/09\/29\/14674.html"},"modified":"2018-03-13T19:06:23","modified_gmt":"2018-03-14T00:06:23","slug":"convection-radiation-confusion","status":"publish","type":"post","link":"https:\/\/www.kith.org\/vardibidian\/2013\/09\/29\/convection-radiation-confusion\/","title":{"rendered":"Convection, radiation, confusion"},"content":{"rendered":"\n

Here’s one in what I hope will not be an ongoing series of posts wondering what the hell is going on in my Perfect Non-Reader’s science homework. See for reference The Opposite of Read<\/a>. So. What’s this a picture of?\n

\"teakettle\"\n

Yes, it’s a teakettle, an image dear to my heart. But the context I am about to provide you with, Gentle Reader, is that it is an image from a worksheet on heat transfer, and the Perfect non-Reader of this Tohu Bohu was asked to indicate whether it was showing convection or radiation. Within that context, then, what’s the picture showing?\n

Is it a picture of steam? Because that would make sense, if you figure it backwards: we want a picture of steam, so we’ll show a teakettle<\/i>. The steam, though, is only a few wavy lines; the center of the picture is the kettle itself. So it’s a picture of the kettle, right?\n

I was trying to count and assess the heat transfers in this picture. For one, of course, there’s the heating element not shown in the picture which is transferring heat to the ceramic (probably) stovetop we do see. Then the stovetop is transferring heat to the body of the kettle. The kettle is transferring heat to the water we don’t see inside the kettle, and the water is transferring heat within itself (by convection, remember?) (Actually, the kettle is transferring heat within itself, too, and also transferring heat to the lid, which we can see is a separate piece, and I must say I hope it’s not transferring too much heat to its handle because ouch) and presumably to whatever air is in the kettle. Then the water is becoming steam, which isn’t a heat transfer as such and then the steam is rising out of the spout and transferring heat to the air surrounding. And of course we can’t really see it, but all of those things that get hot are heating the air around them (by radiation, unless I am really not helping with the homework) even if they aren’t mixing with them the way the steam is. Am I missing any?\n

Really, though, in terms of getting points, it’s a question of what the picture is showing, isn’t it? If it’s a picture of a teakettle, then it’s radiation, and if it’s a picture of steam, then it’s convection, right? Or am I totally misunderstanding the science—which is completely plausible, of course, but even then, I think it’s a fair question: what is it a picture of?\n

Tolerabimus quod tolerare debemus<\/I>,
-Vardibidian.\n\n","protected":false},"excerpt":{"rendered":"

In Which Your Humble Blogger hocks a chaynik, which is funny because a chaynik is literally a teakettle. See, ‘hock a chaynik’ is a Yiddish expression, and\u2014wait, come back, I’m explaining the joke! Where are you going?<\/p>\n","protected":false},"author":7,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[196],"tags":[],"class_list":["post-14674","post","type-post","status-publish","format-standard","hentry","category-hatchet-job"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.kith.org\/vardibidian\/wp-json\/wp\/v2\/posts\/14674","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.kith.org\/vardibidian\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.kith.org\/vardibidian\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.kith.org\/vardibidian\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/www.kith.org\/vardibidian\/wp-json\/wp\/v2\/comments?post=14674"}],"version-history":[{"count":1,"href":"https:\/\/www.kith.org\/vardibidian\/wp-json\/wp\/v2\/posts\/14674\/revisions"}],"predecessor-version":[{"id":16660,"href":"https:\/\/www.kith.org\/vardibidian\/wp-json\/wp\/v2\/posts\/14674\/revisions\/16660"}],"wp:attachment":[{"href":"https:\/\/www.kith.org\/vardibidian\/wp-json\/wp\/v2\/media?parent=14674"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.kith.org\/vardibidian\/wp-json\/wp\/v2\/categories?post=14674"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.kith.org\/vardibidian\/wp-json\/wp\/v2\/tags?post=14674"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}