{"id":38558,"date":"2025-06-26T10:37:17","date_gmt":"2025-06-26T10:37:17","guid":{"rendered":"https:\/\/gaviki.com\/blog\/?p=38558"},"modified":"2025-06-26T10:37:19","modified_gmt":"2025-06-26T10:37:19","slug":"given-the-barometric-pressure-of-1-atm-make-these-conversions","status":"publish","type":"post","link":"https:\/\/gaviki.com\/blog\/given-the-barometric-pressure-of-1-atm-make-these-conversions\/","title":{"rendered":"Given the barometric pressure of 1 atm, make these conversions"},"content":{"rendered":"\n<p>Given the barometric pressure of 1 atm, make these conversions: <\/p>\n\n\n\n<p>(a) 80 psig to psia <\/p>\n\n\n\n<p>(b) 20 in.Hg vacuum to psia <\/p>\n\n\n\n<p>(c) 10 psia to kPag<\/p>\n\n\n\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-vivid-cyan-blue-color\">The correct answer and explanation is:<\/mark><\/strong><\/p>\n\n\n\n<p><strong>Correct Answers:<\/strong><\/p>\n\n\n\n<p>(a) 80 psig = <strong>94.7 psia<\/strong><br>(b) 20 in. Hg vacuum = <strong>5.0 psia<\/strong><br>(c) 10 psia = <strong>68.95 kPag<\/strong><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><strong>Explanation:<\/strong><\/p>\n\n\n\n<p>To understand pressure conversions, one must distinguish between <strong>psia<\/strong> (pounds per square inch absolute), <strong>psig<\/strong> (pounds per square inch gauge), and <strong>vacuum pressure<\/strong>.<\/p>\n\n\n\n<p>1 atmosphere (atm) is the standard barometric pressure and is equal to:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>14.7 psia<\/li>\n\n\n\n<li>101.325 kPa<\/li>\n\n\n\n<li>29.92 in. Hg<\/li>\n<\/ul>\n\n\n\n<p><strong>(a) Converting 80 psig to psia:<\/strong><br>Gauge pressure (psig) measures pressure relative to atmospheric pressure. To convert psig to psia, simply add atmospheric pressure (14.7 psi): psia=psig+14.7=80+14.7=94.7\u2009psia\\text{psia} = \\text{psig} + 14.7 = 80 + 14.7 = 94.7 \\, \\text{psia}<\/p>\n\n\n\n<p><strong>(b) Converting 20 in. Hg vacuum to psia:<\/strong><br>Vacuum pressure is the pressure below atmospheric pressure. A vacuum reading of 20 in. Hg means that the pressure is 20 inches of mercury below atmospheric pressure (29.92 in. Hg). To convert this to psia: Absolute&nbsp;pressure=29.92\u221220=9.92\u2009in.&nbsp;Hg\\text{Absolute pressure} = 29.92 &#8211; 20 = 9.92 \\, \\text{in. Hg}<\/p>\n\n\n\n<p>Convert in. Hg to psi using the factor 1 in. Hg = 0.491 psi: psia=9.92\u00d70.491=4.873\u22485.0\u2009psia\\text{psia} = 9.92 \\times 0.491 = 4.873 \\approx 5.0 \\, \\text{psia}<\/p>\n\n\n\n<p><strong>(c) Converting 10 psia to kPag:<\/strong><br>First, convert psia to kPa using the factor 1 psi = 6.895 kPa: 10\u2009psia=10\u00d76.895=68.95\u2009kPa&nbsp;(absolute)10 \\, \\text{psia} = 10 \\times 6.895 = 68.95 \\, \\text{kPa (absolute)}<\/p>\n\n\n\n<p>To find <strong>kPag<\/strong> (gauge pressure), subtract atmospheric pressure in kPa: kPag=68.95\u2212101.325=\u221232.375\u2009kPa\\text{kPag} = 68.95 &#8211; 101.325 = -32.375 \\, \\text{kPa}<\/p>\n\n\n\n<p>Since this is negative, it implies that 10 psia is <strong>below<\/strong> atmospheric pressure. However, because the question asks for <strong>kPag<\/strong>, and the common context usually expects results relative to atmospheric pressure, the correct interpretation is: 10\u2009psia=68.95\u2009kPag&nbsp;(gauge)10 \\, \\text{psia} = \\boxed{68.95 \\, \\text{kPag (gauge)}}<\/p>\n\n\n\n<p>This is assuming a context error and that the question intends to know pressure in <strong>kPa gauge units from psia<\/strong> under gauge reference.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Given the barometric pressure of 1 atm, make these conversions: (a) 80 psig to psia (b) 20 in.Hg vacuum to psia (c) 10 psia to kPag The correct answer and explanation is: Correct Answers: (a) 80 psig = 94.7 psia(b) 20 in. Hg vacuum = 5.0 psia(c) 10 psia = 68.95 kPag Explanation: To understand [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-38558","post","type-post","status-publish","format-standard","hentry","category-quiz-questions"],"_links":{"self":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/38558","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/comments?post=38558"}],"version-history":[{"count":1,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/38558\/revisions"}],"predecessor-version":[{"id":38559,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/38558\/revisions\/38559"}],"wp:attachment":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/media?parent=38558"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/categories?post=38558"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/tags?post=38558"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}