{"id":88153,"date":"2025-06-01T07:03:32","date_gmt":"2025-06-01T07:03:32","guid":{"rendered":"https:\/\/exam.pscnotes.com\/mcq\/?p=88153"},"modified":"2025-06-01T07:03:32","modified_gmt":"2025-06-01T07:03:32","slug":"three-equal-resistances-when-combined-in-series-are-equivalent-to-90-o","status":"publish","type":"post","link":"https:\/\/exam.pscnotes.com\/mcq\/three-equal-resistances-when-combined-in-series-are-equivalent-to-90-o\/","title":{"rendered":"Three equal resistances when combined in series are equivalent to 90 o"},"content":{"rendered":"

Three equal resistances when combined in series are equivalent to 90 ohm. Their equivalent resistance when combined in parallel will be:<\/p>\n

[amp_mcq option1=”10 ohm” option2=”30 ohm” option3=”270 ohm” option4=”810 ohm” correct=”option1″]<\/p>\n

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\n
This question was previously asked in<\/div>\n
UPSC NDA-2 – 2015<\/div>\n<\/div>\n
Download PDF<\/a>Attempt Online<\/a><\/div>\n<\/div>\n
\nLet R be the resistance of each of the three equal resistors. When connected in series, the equivalent resistance (Rs) is the sum of individual resistances: Rs = R + R + R = 3R. Given Rs = 90 ohm, we have 3R = 90 ohm, so R = 30 ohm. When the three equal resistors are connected in parallel, the equivalent resistance (Rp) is given by the formula 1\/Rp = 1\/R + 1\/R + 1\/R = 3\/R. Thus, Rp = R\/3. Substituting R = 30 ohm, we get Rp = 30 ohm \/ 3 = 10 ohm.
\n<\/section>\n
\nCalculation of equivalent resistance for resistors connected in series and parallel.
\n<\/section>\n
\nFor N equal resistors of resistance R, the equivalent resistance in series is NR, and the equivalent resistance in parallel is R\/N.
\n<\/section>\n","protected":false},"excerpt":{"rendered":"

Three equal resistances when combined in series are equivalent to 90 ohm. Their equivalent resistance when combined in parallel will be: [amp_mcq option1=”10 ohm” option2=”30 ohm” option3=”270 ohm” option4=”810 ohm” correct=”option1″] This question was previously asked in UPSC NDA-2 – 2015 Download PDFAttempt Online Let R be the resistance of each of the three equal … <\/p>\n

Detailed SolutionThree equal resistances when combined in series are equivalent to 90 o<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1094],"tags":[1443,1201,1128],"class_list":["post-88153","post","type-post","status-publish","format-standard","hentry","category-upsc-nda-2","tag-1443","tag-electric-current","tag-physics","no-featured-image-padding"],"yoast_head":"\nThree equal resistances when combined in series are equivalent to 90 o<\/title>\n<meta name=\"description\" content=\"Let R be the resistance of each of the three equal resistors. When connected in series, the equivalent resistance (Rs) is the sum of individual resistances: Rs = R + R + R = 3R. Given Rs = 90 ohm, we have 3R = 90 ohm, so R = 30 ohm. When the three equal resistors are connected in parallel, the equivalent resistance (Rp) is given by the formula 1\/Rp = 1\/R + 1\/R + 1\/R = 3\/R. Thus, Rp = R\/3. Substituting R = 30 ohm, we get Rp = 30 ohm \/ 3 = 10 ohm. Calculation of equivalent resistance for resistors connected in series and parallel.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/exam.pscnotes.com\/mcq\/three-equal-resistances-when-combined-in-series-are-equivalent-to-90-o\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Three equal resistances when combined in series are equivalent to 90 o\" \/>\n<meta property=\"og:description\" content=\"Let R be the resistance of each of the three equal resistors. When connected in series, the equivalent resistance (Rs) is the sum of individual resistances: Rs = R + R + R = 3R. Given Rs = 90 ohm, we have 3R = 90 ohm, so R = 30 ohm. When the three equal resistors are connected in parallel, the equivalent resistance (Rp) is given by the formula 1\/Rp = 1\/R + 1\/R + 1\/R = 3\/R. Thus, Rp = R\/3. Substituting R = 30 ohm, we get Rp = 30 ohm \/ 3 = 10 ohm. Calculation of equivalent resistance for resistors connected in series and parallel.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/exam.pscnotes.com\/mcq\/three-equal-resistances-when-combined-in-series-are-equivalent-to-90-o\/\" \/>\n<meta property=\"og:site_name\" content=\"MCQ and Quiz for Exams\" \/>\n<meta property=\"article:published_time\" content=\"2025-06-01T07:03:32+00:00\" \/>\n<meta name=\"author\" content=\"rawan239\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"rawan239\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"1 minute\" \/>\n<!-- \/ Yoast SEO Premium plugin. -->","yoast_head_json":{"title":"Three equal resistances when combined in series are equivalent to 90 o","description":"Let R be the resistance of each of the three equal resistors. When connected in series, the equivalent resistance (Rs) is the sum of individual resistances: Rs = R + R + R = 3R. Given Rs = 90 ohm, we have 3R = 90 ohm, so R = 30 ohm. When the three equal resistors are connected in parallel, the equivalent resistance (Rp) is given by the formula 1\/Rp = 1\/R + 1\/R + 1\/R = 3\/R. Thus, Rp = R\/3. Substituting R = 30 ohm, we get Rp = 30 ohm \/ 3 = 10 ohm. Calculation of equivalent resistance for resistors connected in series and parallel.","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/exam.pscnotes.com\/mcq\/three-equal-resistances-when-combined-in-series-are-equivalent-to-90-o\/","og_locale":"en_US","og_type":"article","og_title":"Three equal resistances when combined in series are equivalent to 90 o","og_description":"Let R be the resistance of each of the three equal resistors. When connected in series, the equivalent resistance (Rs) is the sum of individual resistances: Rs = R + R + R = 3R. Given Rs = 90 ohm, we have 3R = 90 ohm, so R = 30 ohm. When the three equal resistors are connected in parallel, the equivalent resistance (Rp) is given by the formula 1\/Rp = 1\/R + 1\/R + 1\/R = 3\/R. Thus, Rp = R\/3. Substituting R = 30 ohm, we get Rp = 30 ohm \/ 3 = 10 ohm. Calculation of equivalent resistance for resistors connected in series and parallel.","og_url":"https:\/\/exam.pscnotes.com\/mcq\/three-equal-resistances-when-combined-in-series-are-equivalent-to-90-o\/","og_site_name":"MCQ and Quiz for Exams","article_published_time":"2025-06-01T07:03:32+00:00","author":"rawan239","twitter_card":"summary_large_image","twitter_misc":{"Written by":"rawan239","Est. reading time":"1 minute"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/exam.pscnotes.com\/mcq\/three-equal-resistances-when-combined-in-series-are-equivalent-to-90-o\/","url":"https:\/\/exam.pscnotes.com\/mcq\/three-equal-resistances-when-combined-in-series-are-equivalent-to-90-o\/","name":"Three equal resistances when combined in series are equivalent to 90 o","isPartOf":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/#website"},"datePublished":"2025-06-01T07:03:32+00:00","dateModified":"2025-06-01T07:03:32+00:00","author":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/#\/schema\/person\/5807dafeb27d2ec82344d6cbd6c3d209"},"description":"Let R be the resistance of each of the three equal resistors. When connected in series, the equivalent resistance (Rs) is the sum of individual resistances: Rs = R + R + R = 3R. Given Rs = 90 ohm, we have 3R = 90 ohm, so R = 30 ohm. When the three equal resistors are connected in parallel, the equivalent resistance (Rp) is given by the formula 1\/Rp = 1\/R + 1\/R + 1\/R = 3\/R. Thus, Rp = R\/3. Substituting R = 30 ohm, we get Rp = 30 ohm \/ 3 = 10 ohm. Calculation of equivalent resistance for resistors connected in series and parallel.","breadcrumb":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/three-equal-resistances-when-combined-in-series-are-equivalent-to-90-o\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/exam.pscnotes.com\/mcq\/three-equal-resistances-when-combined-in-series-are-equivalent-to-90-o\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/exam.pscnotes.com\/mcq\/three-equal-resistances-when-combined-in-series-are-equivalent-to-90-o\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/exam.pscnotes.com\/mcq\/"},{"@type":"ListItem","position":2,"name":"UPSC NDA-2","item":"https:\/\/exam.pscnotes.com\/mcq\/category\/upsc-nda-2\/"},{"@type":"ListItem","position":3,"name":"Three equal resistances when combined in series are equivalent to 90 o"}]},{"@type":"WebSite","@id":"https:\/\/exam.pscnotes.com\/mcq\/#website","url":"https:\/\/exam.pscnotes.com\/mcq\/","name":"MCQ and Quiz for Exams","description":"","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/exam.pscnotes.com\/mcq\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"en-US"},{"@type":"Person","@id":"https:\/\/exam.pscnotes.com\/mcq\/#\/schema\/person\/5807dafeb27d2ec82344d6cbd6c3d209","name":"rawan239","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/exam.pscnotes.com\/mcq\/#\/schema\/person\/image\/","url":"https:\/\/secure.gravatar.com\/avatar\/761a7274f9cce048fa5b921221e7934820d74514df93ef195a9d22af0c1c9001?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/761a7274f9cce048fa5b921221e7934820d74514df93ef195a9d22af0c1c9001?s=96&d=mm&r=g","caption":"rawan239"},"sameAs":["https:\/\/exam.pscnotes.com"],"url":"https:\/\/exam.pscnotes.com\/mcq\/author\/rawan239\/"}]}},"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/posts\/88153","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/comments?post=88153"}],"version-history":[{"count":0,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/posts\/88153\/revisions"}],"wp:attachment":[{"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/media?parent=88153"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/categories?post=88153"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/tags?post=88153"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}