{"id":209248,"date":"2025-04-29T03:55:41","date_gmt":"2025-04-29T03:55:41","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=209248"},"modified":"2025-04-29T03:55:44","modified_gmt":"2025-04-29T03:55:44","slug":"for-a-microscope-on-which-17-ocular-units-align-with-100-%ce%bc-m-on-the-stage-micrometer-when-the-4x-objective-is-used","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/04\/29\/for-a-microscope-on-which-17-ocular-units-align-with-100-%ce%bc-m-on-the-stage-micrometer-when-the-4x-objective-is-used\/","title":{"rendered":"For a microscope on which 17 ocular units align with 100 \u03bc m on the stage micrometer when the 4x objective is used"},"content":{"rendered":"\n<p>For a microscope on which 17 ocular units align with 100 \u03bc m on the stage micrometer when the 4x objective is used, how many micrometers are there per ocular unit when using the (a) 4x objective, (b) 10x objective, (c) 45x objective, and (d) 97x objective?<\/p>\n\n\n\n<p><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-6-color\"><strong>The correct answer and explanation is :<\/strong><\/mark><\/p>\n\n\n\n<p>Let&#8217;s work through the problem carefully:<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><strong>Given:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>17 ocular units<\/strong> align with <strong>100 \u03bcm<\/strong> on the stage micrometer when using the <strong>4x objective<\/strong>.<\/li>\n<\/ul>\n\n\n\n<p>First, find the size (in micrometers) of <strong>one ocular unit<\/strong> at <strong>4x<\/strong>:<\/p>\n\n\n\n<p>[<br>\\text{Size per ocular unit at 4x} = \\frac{100\\ \\mu m}{17} \\approx 5.88\\ \\mu m<br>]<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p>Now, when you change the objective lens (to 10x, 45x, or 97x), <strong>the number of micrometers per ocular unit decreases proportionally<\/strong> because magnification increases.<\/p>\n\n\n\n<p>Since <strong>magnification and field size are inversely proportional<\/strong>, we can calculate the new micrometers per ocular unit by adjusting for the ratio of magnifications:<\/p>\n\n\n\n<p>The formula:<\/p>\n\n\n\n<p>[<br>\\text{New micrometers per ocular unit} = \\text{(Micrometers per ocular unit at 4x)} \\times \\frac{4}{\\text{New objective magnification}}<br>]<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">(a) 4x Objective<\/h3>\n\n\n\n<p>Already calculated:<\/p>\n\n\n\n<p>[<br>5.88\\ \\mu m\\ \\text{per ocular unit}<br>]<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">(b) 10x Objective<\/h3>\n\n\n\n<p>[<br>5.88\\ \\mu m \\times \\frac{4}{10} = 2.35\\ \\mu m\\ \\text{per ocular unit}<br>]<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">(c) 45x Objective<\/h3>\n\n\n\n<p>[<br>5.88\\ \\mu m \\times \\frac{4}{45} \\approx 0.523\\ \\mu m\\ \\text{per ocular unit}<br>]<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">(d) 97x Objective<\/h3>\n\n\n\n<p>[<br>5.88\\ \\mu m \\times \\frac{4}{97} \\approx 0.242\\ \\mu m\\ \\text{per ocular unit}<br>]<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Final Answers:<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>(a) 5.88 \u03bcm per ocular unit (4x objective)<\/li>\n\n\n\n<li>(b) 2.35 \u03bcm per ocular unit (10x objective)<\/li>\n\n\n\n<li>(c) 0.523 \u03bcm per ocular unit (45x objective)<\/li>\n\n\n\n<li>(d) 0.242 \u03bcm per ocular unit (97x objective)<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Explanation (300+ words)<\/strong><\/h3>\n\n\n\n<p>In microscopy, calibration is essential to accurately measure the size of specimens. Calibration typically uses a <strong>stage micrometer<\/strong>, a microscope slide with a precisely ruled scale (usually in micrometers), and the <strong>ocular micrometer<\/strong>, which is a glass disk with an arbitrary scale inserted into the microscope eyepiece.<\/p>\n\n\n\n<p>The relationship between the ocular micrometer units and actual distances must be established for each objective lens because <strong>magnification changes the apparent size<\/strong> of features. The higher the magnification, the smaller the actual size represented by each ocular division.<\/p>\n\n\n\n<p>In this problem, it is given that with the 4x objective, 17 ocular units line up with 100 \u03bcm on the stage micrometer. Dividing 100 \u03bcm by 17 gives approximately 5.88 \u03bcm per ocular unit at 4x magnification.<\/p>\n\n\n\n<p>When you switch objectives, the apparent size of an object increases (higher magnification), so each ocular division represents a <strong>smaller real distance<\/strong>. Since magnification and measured size are inversely proportional, we adjust by multiplying the original calibration (5.88 \u03bcm) by the ratio of the original magnification (4x) to the new magnification.<\/p>\n\n\n\n<p>Thus, when switching to 10x, the value per ocular unit decreases to 2.35 \u03bcm. At 45x, it further decreases to about 0.523 \u03bcm, and at 97x, it becomes about 0.242 \u03bcm per ocular unit.<\/p>\n\n\n\n<p>This method ensures accurate measurement at any magnification without needing to recalibrate each time physically. However, for highly precise work (like research microscopy), calibration is often repeated at each magnification to account for slight mechanical imperfections.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>For a microscope on which 17 ocular units align with 100 \u03bc m on the stage micrometer when the 4x objective is used, how many micrometers are there per ocular unit when using the (a) 4x objective, (b) 10x objective, (c) 45x objective, and (d) 97x objective? The correct answer and explanation is : Let&#8217;s [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-209248","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/209248","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=209248"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/209248\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=209248"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=209248"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=209248"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}