{"id":946,"date":"2014-01-04T12:02:34","date_gmt":"2014-01-04T19:02:34","guid":{"rendered":"http:\/\/daryllafferty.com\/blog\/?p=946"},"modified":"2014-01-04T12:02:34","modified_gmt":"2014-01-04T19:02:34","slug":"physics-misconceptions","status":"publish","type":"post","link":"https:\/\/daryllafferty.com\/blog\/2014\/01\/04\/physics-misconceptions\/","title":{"rendered":"Physics Misconceptions"},"content":{"rendered":"<p><strong>How do airplanes fly?<\/strong><br \/>\nI was taught in high school that the reason a wing provides lift is because the top is curved more than the bottom and that the air flowing faster over the top has less pressure.  There is some truth to that, but the major source of lift is angle of attack, the front of the wing being higher than the rear.  As a child I experimented with this effect by sticking my hand out the window of a moving car and noticing how the air would strongly push my hand up or down depending on how I positioned it.  The curved top of a wing helps to smooth out the airflow and reduce turbulence and drag, but has a smaller effect on lift.  If you doubt this, then consider how a plane can fly upside down.  It&#8217;s not quite as efficient because the airfoil is working against you, but angle of attack easily counteracts that.<\/p>\n<p><strong>Why does a meteor burn up?<\/strong><br \/>\nWe frequently hear that a meteor or re-entering spacecraft heats up because of &#8220;friction&#8221; with the air.  It&#8217;s true that the object moving through the air will generate some heat from the air rubbing against its sides, but most of the heat is generated by the air being compressed in the front (i.e. &#8220;<a href=\"http:\/\/en.wikipedia.org\/wiki\/Ram_pressure\" title=\"Ram Pressure\">Ram Pressure<\/a>&#8220;).  As the meteor enters the atmosphere, air in front is unable to move out of the way as quickly as the meteor is falling, and the air gets extremely compressed.  Compressing a gas raises its temperature.  Think about where the heat shield is on the old Mercury or Apollo capsules: On the bottom surface that leads its descent.  The sides of the capsule are much less insulated because the air flowing over the sides adds little heat.  <\/p>\n","protected":false},"excerpt":{"rendered":"<p>How do airplanes fly? I was taught in high school that the reason a wing provides lift is because the top is curved more than the bottom and that the air flowing faster over the top has less pressure. There is some truth to that, but the major source of lift is angle of attack, [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[],"class_list":["post-946","post","type-post","status-publish","format-standard","hentry","category-computers"],"_links":{"self":[{"href":"https:\/\/daryllafferty.com\/blog\/wp-json\/wp\/v2\/posts\/946","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/daryllafferty.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/daryllafferty.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/daryllafferty.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/daryllafferty.com\/blog\/wp-json\/wp\/v2\/comments?post=946"}],"version-history":[{"count":4,"href":"https:\/\/daryllafferty.com\/blog\/wp-json\/wp\/v2\/posts\/946\/revisions"}],"predecessor-version":[{"id":950,"href":"https:\/\/daryllafferty.com\/blog\/wp-json\/wp\/v2\/posts\/946\/revisions\/950"}],"wp:attachment":[{"href":"https:\/\/daryllafferty.com\/blog\/wp-json\/wp\/v2\/media?parent=946"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/daryllafferty.com\/blog\/wp-json\/wp\/v2\/categories?post=946"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/daryllafferty.com\/blog\/wp-json\/wp\/v2\/tags?post=946"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}