{"id":88839,"date":"2025-06-01T07:23:14","date_gmt":"2025-06-01T07:23:14","guid":{"rendered":"https:\/\/exam.pscnotes.com\/mcq\/?p=88839"},"modified":"2025-06-01T07:23:14","modified_gmt":"2025-06-01T07:23:14","slug":"which-one-of-the-following-statements-regarding-a-current-carrying-sol","status":"publish","type":"post","link":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-statements-regarding-a-current-carrying-sol\/","title":{"rendered":"Which one of the following statements regarding a current-carrying sol"},"content":{"rendered":"

Which one of the following statements regarding a current-carrying solenoid is not<\/b> correct?<\/p>\n

[amp_mcq option1=”The magnetic field inside the solenoid is uniform.” option2=”The current-carrying solenoid behaves like a bar magnet.” option3=”The magnetic field inside the solenoid increases with increase in current.” option4=”If a soft iron bar is inserted inside the solenoid, the magnetic field remains the same.” correct=”option4″]<\/p>\n

\n
\n
This question was previously asked in<\/div>\n
UPSC NDA-2 – 2022<\/div>\n<\/div>\n
Download PDF<\/a>Attempt Online<\/a><\/div>\n<\/div>\n
\nLet’s analyze each statement about a current-carrying solenoid:
\nA) The magnetic field inside a *long* solenoid is approximately uniform and directed along the axis of the solenoid, except near the ends. This statement is correct for an ideal or long solenoid.
\nB) A current-carrying solenoid creates a magnetic field pattern similar to that of a bar magnet, with magnetic poles at its ends. This statement is correct.
\nC) The magnitude of the magnetic field inside a solenoid is given by $B = \\mu n I$, where $\\mu$ is the permeability of the core material, $n$ is the number of turns per unit length, and $I$ is the current. The field is directly proportional to the current ($I$). So, increasing the current increases the magnetic field. This statement is correct.
\nD) If a soft iron bar (a ferromagnetic material with high permeability) is inserted inside the solenoid, the magnetic field inside increases significantly. This happens because the soft iron gets strongly magnetized in the direction of the solenoid’s field, and its own magnetic field adds to the field produced by the current. The permeability of soft iron is much greater than the permeability of air or vacuum ($\\mu >> \\mu_0$). The magnetic field does *not* remain the same; it increases. This statement is incorrect.
\n<\/section>\n
\nFerromagnetic materials like soft iron dramatically increase the magnetic field strength when placed inside a solenoid or coil because they become strongly magnetized, effectively increasing the magnetic permeability of the core.
\n<\/section>\n
\nThis property is used to make electromagnets, where a soft iron core is inserted into a solenoid to produce a very strong magnetic field when current flows.
\n<\/section>\n","protected":false},"excerpt":{"rendered":"

Which one of the following statements regarding a current-carrying solenoid is not correct? [amp_mcq option1=”The magnetic field inside the solenoid is uniform.” option2=”The current-carrying solenoid behaves like a bar magnet.” option3=”The magnetic field inside the solenoid increases with increase in current.” option4=”If a soft iron bar is inserted inside the solenoid, the magnetic field remains … <\/p>\n

Detailed SolutionWhich one of the following statements regarding a current-carrying sol<\/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":[1108,1201,1128],"class_list":["post-88839","post","type-post","status-publish","format-standard","hentry","category-upsc-nda-2","tag-1108","tag-electric-current","tag-physics","no-featured-image-padding"],"yoast_head":"\nWhich one of the following statements regarding a current-carrying sol<\/title>\n<meta name=\"description\" content=\"Let's analyze each statement about a current-carrying solenoid: A) The magnetic field inside a *long* solenoid is approximately uniform and directed along the axis of the solenoid, except near the ends. This statement is correct for an ideal or long solenoid. B) A current-carrying solenoid creates a magnetic field pattern similar to that of a bar magnet, with magnetic poles at its ends. This statement is correct. C) The magnitude of the magnetic field inside a solenoid is given by $B = mu n I$, where $mu$ is the permeability of the core material, $n$ is the number of turns per unit length, and $I$ is the current. The field is directly proportional to the current ($I$). So, increasing the current increases the magnetic field. This statement is correct. D) If a soft iron bar (a ferromagnetic material with high permeability) is inserted inside the solenoid, the magnetic field inside increases significantly. This happens because the soft iron gets strongly magnetized in the direction of the solenoid's field, and its own magnetic field adds to the field produced by the current. The permeability of soft iron is much greater than the permeability of air or vacuum ($mu >> mu_0$). The magnetic field does *not* remain the same; it increases. This statement is incorrect. Ferromagnetic materials like soft iron dramatically increase the magnetic field strength when placed inside a solenoid or coil because they become strongly magnetized, effectively increasing the magnetic permeability of the core.\" \/>\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\/which-one-of-the-following-statements-regarding-a-current-carrying-sol\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Which one of the following statements regarding a current-carrying sol\" \/>\n<meta property=\"og:description\" content=\"Let's analyze each statement about a current-carrying solenoid: A) The magnetic field inside a *long* solenoid is approximately uniform and directed along the axis of the solenoid, except near the ends. This statement is correct for an ideal or long solenoid. B) A current-carrying solenoid creates a magnetic field pattern similar to that of a bar magnet, with magnetic poles at its ends. This statement is correct. C) The magnitude of the magnetic field inside a solenoid is given by $B = mu n I$, where $mu$ is the permeability of the core material, $n$ is the number of turns per unit length, and $I$ is the current. The field is directly proportional to the current ($I$). So, increasing the current increases the magnetic field. This statement is correct. D) If a soft iron bar (a ferromagnetic material with high permeability) is inserted inside the solenoid, the magnetic field inside increases significantly. This happens because the soft iron gets strongly magnetized in the direction of the solenoid's field, and its own magnetic field adds to the field produced by the current. The permeability of soft iron is much greater than the permeability of air or vacuum ($mu >> mu_0$). The magnetic field does *not* remain the same; it increases. This statement is incorrect. Ferromagnetic materials like soft iron dramatically increase the magnetic field strength when placed inside a solenoid or coil because they become strongly magnetized, effectively increasing the magnetic permeability of the core.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-statements-regarding-a-current-carrying-sol\/\" \/>\n<meta property=\"og:site_name\" content=\"MCQ and Quiz for Exams\" \/>\n<meta property=\"article:published_time\" content=\"2025-06-01T07:23:14+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=\"2 minutes\" \/>\n<!-- \/ Yoast SEO Premium plugin. -->","yoast_head_json":{"title":"Which one of the following statements regarding a current-carrying sol","description":"Let's analyze each statement about a current-carrying solenoid: A) The magnetic field inside a *long* solenoid is approximately uniform and directed along the axis of the solenoid, except near the ends. This statement is correct for an ideal or long solenoid. B) A current-carrying solenoid creates a magnetic field pattern similar to that of a bar magnet, with magnetic poles at its ends. This statement is correct. C) The magnitude of the magnetic field inside a solenoid is given by $B = mu n I$, where $mu$ is the permeability of the core material, $n$ is the number of turns per unit length, and $I$ is the current. The field is directly proportional to the current ($I$). So, increasing the current increases the magnetic field. This statement is correct. D) If a soft iron bar (a ferromagnetic material with high permeability) is inserted inside the solenoid, the magnetic field inside increases significantly. This happens because the soft iron gets strongly magnetized in the direction of the solenoid's field, and its own magnetic field adds to the field produced by the current. The permeability of soft iron is much greater than the permeability of air or vacuum ($mu >> mu_0$). The magnetic field does *not* remain the same; it increases. This statement is incorrect. Ferromagnetic materials like soft iron dramatically increase the magnetic field strength when placed inside a solenoid or coil because they become strongly magnetized, effectively increasing the magnetic permeability of the core.","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\/which-one-of-the-following-statements-regarding-a-current-carrying-sol\/","og_locale":"en_US","og_type":"article","og_title":"Which one of the following statements regarding a current-carrying sol","og_description":"Let's analyze each statement about a current-carrying solenoid: A) The magnetic field inside a *long* solenoid is approximately uniform and directed along the axis of the solenoid, except near the ends. This statement is correct for an ideal or long solenoid. B) A current-carrying solenoid creates a magnetic field pattern similar to that of a bar magnet, with magnetic poles at its ends. This statement is correct. C) The magnitude of the magnetic field inside a solenoid is given by $B = mu n I$, where $mu$ is the permeability of the core material, $n$ is the number of turns per unit length, and $I$ is the current. The field is directly proportional to the current ($I$). So, increasing the current increases the magnetic field. This statement is correct. D) If a soft iron bar (a ferromagnetic material with high permeability) is inserted inside the solenoid, the magnetic field inside increases significantly. This happens because the soft iron gets strongly magnetized in the direction of the solenoid's field, and its own magnetic field adds to the field produced by the current. The permeability of soft iron is much greater than the permeability of air or vacuum ($mu >> mu_0$). The magnetic field does *not* remain the same; it increases. This statement is incorrect. Ferromagnetic materials like soft iron dramatically increase the magnetic field strength when placed inside a solenoid or coil because they become strongly magnetized, effectively increasing the magnetic permeability of the core.","og_url":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-statements-regarding-a-current-carrying-sol\/","og_site_name":"MCQ and Quiz for Exams","article_published_time":"2025-06-01T07:23:14+00:00","author":"rawan239","twitter_card":"summary_large_image","twitter_misc":{"Written by":"rawan239","Est. reading time":"2 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-statements-regarding-a-current-carrying-sol\/","url":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-statements-regarding-a-current-carrying-sol\/","name":"Which one of the following statements regarding a current-carrying sol","isPartOf":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/#website"},"datePublished":"2025-06-01T07:23:14+00:00","dateModified":"2025-06-01T07:23:14+00:00","author":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/#\/schema\/person\/5807dafeb27d2ec82344d6cbd6c3d209"},"description":"Let's analyze each statement about a current-carrying solenoid: A) The magnetic field inside a *long* solenoid is approximately uniform and directed along the axis of the solenoid, except near the ends. This statement is correct for an ideal or long solenoid. B) A current-carrying solenoid creates a magnetic field pattern similar to that of a bar magnet, with magnetic poles at its ends. This statement is correct. C) The magnitude of the magnetic field inside a solenoid is given by $B = \\mu n I$, where $\\mu$ is the permeability of the core material, $n$ is the number of turns per unit length, and $I$ is the current. The field is directly proportional to the current ($I$). So, increasing the current increases the magnetic field. This statement is correct. D) If a soft iron bar (a ferromagnetic material with high permeability) is inserted inside the solenoid, the magnetic field inside increases significantly. This happens because the soft iron gets strongly magnetized in the direction of the solenoid's field, and its own magnetic field adds to the field produced by the current. The permeability of soft iron is much greater than the permeability of air or vacuum ($\\mu >> \\mu_0$). The magnetic field does *not* remain the same; it increases. This statement is incorrect. Ferromagnetic materials like soft iron dramatically increase the magnetic field strength when placed inside a solenoid or coil because they become strongly magnetized, effectively increasing the magnetic permeability of the core.","breadcrumb":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-statements-regarding-a-current-carrying-sol\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-statements-regarding-a-current-carrying-sol\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-statements-regarding-a-current-carrying-sol\/#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":"Which one of the following statements regarding a current-carrying sol"}]},{"@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\/88839","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=88839"}],"version-history":[{"count":0,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/posts\/88839\/revisions"}],"wp:attachment":[{"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/media?parent=88839"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/categories?post=88839"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/tags?post=88839"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}