{"id":5441,"date":"2023-01-19T22:00:00","date_gmt":"2023-01-19T22:00:00","guid":{"rendered":"https:\/\/modernsciences.org\/staging\/4414\/?p=5441"},"modified":"2023-01-11T07:41:36","modified_gmt":"2023-01-11T07:41:36","slug":"fancy-a-cup-of-coffee-heres-how-your-electric-kettle-knows-when-your-water-is-boiling","status":"publish","type":"post","link":"https:\/\/modernsciences.org\/staging\/4414\/fancy-a-cup-of-coffee-heres-how-your-electric-kettle-knows-when-your-water-is-boiling\/","title":{"rendered":"Fancy a Cup of Coffee? Here\u2019s How Your Electric Kettle Knows When Your Water Is Boiling"},"content":{"rendered":"\n<p>Imagine your morning going as follows: you wake up, proceed to the nearest countertop, and decide that your day should commence with the regular opening ceremony that consists of brewing your first cup of coffee. You bring out your electric kettle to heat up some water and proceed to fill it up and get it running.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img  loading=\"lazy\"  decoding=\"async\"  width=\"576\"  height=\"1024\"  src=\"https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-4-45x80.png\"  alt=\"\"  class=\"wp-image-5443 pk-lqip pk-lazyload\"  data-pk-sizes=\"auto\"  data-ls-sizes=\"auto, (max-width: 576px) 100vw, 576px\"  data-pk-src=\"https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-4-576x1024.png\"  data-pk-srcset=\"https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-4-576x1024.png 576w, https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-4-169x300.png 169w, https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-4-768x1365.png 768w, https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-4-864x1536.png 864w, https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-4-380x676.png 380w, https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-4-800x1422.png 800w, https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-4-80x142.png 80w, https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-4-45x80.png 45w, https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-4-760x1351.png 760w, https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-4-338x600.png 338w, https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-4.png 1152w\" ><figcaption class=\"wp-element-caption\">Electric kettles are a staple in most homes worldwide and are used on a regular basis for hot drinks like tea and coffee. (Yokomizo, 2020)<\/figcaption><\/figure>\n\n\n\n<p>This, then, may have some of you wondering how your particular \u201csimple\u201d kettle works when you swear it doesn\u2019t have any onboard computer that precisely measures how hot the water is. Turns out, it still has a sensor inside it\u2014it just relies on physics and materials science.<\/p>\n\n\n\n<p>These particular types of thermostats are called <em>bimetallic thermostats<\/em>, and as their name suggests, they are composed of two dissimilar metals. These dissimilar metals, of course, expand when heated at different rates\u2014an effect of their different thermal expansion coefficients.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img  loading=\"lazy\"  decoding=\"async\"  width=\"280\"  height=\"280\"  src=\"https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-3-80x80.png\"  alt=\"\"  class=\"wp-image-5442 pk-lqip pk-lazyload\"  data-pk-sizes=\"auto\"  data-ls-sizes=\"auto, (max-width: 280px) 100vw, 280px\"  data-pk-src=\"https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-3.png\"  data-pk-srcset=\"https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-3.png 280w, https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-3-150x150.png 150w, https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-3-80x80.png 80w, https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-3-110x110.png 110w, https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-3-160x160.png 160w, https:\/\/modernsciences.org\/staging\/4414\/wp-content\/uploads\/2023\/01\/image-3-220x220.png 220w\" ><figcaption class=\"wp-element-caption\">The bimetallic thermostat, shown above, &#8220;snaps&#8221; from one direction to the other when heated to a particular point\u2014the boiling point of water, in the case of an electric kettle. (explainthatstuff.com)<\/figcaption><\/figure>\n<\/div>\n\n\n<p>From here, it\u2019s just a matter of finding the right combination of metals. As the steam rises above the boiling water and enters the inner cavity of the kettle through a hole inside the vessel, it hits the bimetallic thermostat. This causes the thermostat, which is initially bent away from a nearby switch, to suddenly snap in the other direction\u2014think of an umbrella suddenly turning inside out due to strong wind\u2014and hits the nearby switch. This trips the switch, stopping the heating element.<\/p>\n\n\n\n<p>This, then, leaves you with boiling-hot water and a kitchen that isn\u2019t on fire; the bimetallic thermostat works precisely because it was designed to snap from one direction to the other when it heats up to the temperature at which water boils. Physics and materials science at work!<\/p>\n\n\n\n<figure class=\"wp-block-embed aligncenter is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe loading=\"lazy\" title=\"How does an Electric Tea Kettle know when to turn off?\" width=\"1200\" height=\"675\" src=\"https:\/\/www.youtube.com\/embed\/1RAIh11kr2c?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" allowfullscreen><\/iframe>\n<\/div><figcaption class=\"wp-element-caption\">(ScottiesTech.Info, 2017)<\/figcaption><\/figure>\n\n\n\n<p>That\u2019s what engineering is all about\u2014it takes what we find out from science, and churns out methods and devices that use those concepts and phenomena to help us out as we go about our daily lives. Maybe give it some more thought over your next cup of coffee in the morning?<\/p>\n\n\n\n<h4 id=\"references\" class=\"wp-block-heading\">References<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Leigh, K. (2022, February 21). <em>How stuff works: Your kettle<\/em>. The Origin Blog. <a href=\"https:\/\/www.originenergy.com.au\/blog\/how-stuff-works-your-kettle\/\" target=\"_blank\" rel=\"noopener\" title=\"\">https:\/\/www.originenergy.com.au\/blog\/how-stuff-works-your-kettle\/<\/a><\/li>\n\n\n\n<li>Woodford, C. (2011, January 7). <em>How do electric kettles work?<\/em> Explain That Stuff. <a href=\"http:\/\/www.explainthatstuff.com\/how-electric-kettles-work.html\" target=\"_blank\" rel=\"noopener\" title=\"\">http:\/\/www.explainthatstuff.com\/how-electric-kettles-work.html<\/a><\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"Imagine your morning going as follows: you wake up, proceed to the nearest countertop, and decide that your&hellip;\n","protected":false},"author":2,"featured_media":5409,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"nf_dc_page":"","fifu_image_url":"","fifu_image_alt":"","footnotes":""},"categories":[15,17],"tags":[138,204],"class_list":{"0":"post-5441","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-engineering","8":"category-math-and-the-sciences","9":"tag-materials-science","10":"tag-physics","11":"cs-entry","12":"cs-video-wrap"},"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/posts\/5441","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/comments?post=5441"}],"version-history":[{"count":1,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/posts\/5441\/revisions"}],"predecessor-version":[{"id":5444,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/posts\/5441\/revisions\/5444"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/media\/5409"}],"wp:attachment":[{"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/media?parent=5441"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/categories?post=5441"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/tags?post=5441"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}