{"id":4484,"date":"2018-09-11T16:14:26","date_gmt":"2018-09-11T23:14:26","guid":{"rendered":"https:\/\/gurumuda.net\/physics\/?p=4484"},"modified":"2018-09-11T16:14:26","modified_gmt":"2018-09-11T23:14:26","slug":"determining-the-electric-field-using-gauss-law","status":"publish","type":"post","link":"https:\/\/gurumuda.net\/physics\/determining-the-electric-field-using-gauss-law.htm","title":{"rendered":"Determining the electric field using Gauss law","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"<h3 align=\"justify\"><span style=\"font-family: times new roman, times, serif\">Article about\u00a0Determining the electric field using Gauss law<\/span><\/h3>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\"><b><a href=\"https:\/\/gurumuda.net\/physics\/electric-field-problems-and-solutions.htm\">Electric field<\/a> by a single point charge<\/b><\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\"><img loading=\"lazy\" decoding=\"async\" class=\"alignleft size-full wp-image-4485\" src=\"https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/2018\/09\/Determining-the-electric-field-using-Gausss-law-1.png\" alt=\"Determining the electric field using Gauss's law 1\" width=\"112\" height=\"99\" \/>To calculate the electric field produced by a single positive charge, the first step is to select the spherical Gauss surface with radius r where the center of the sphere is at the single charge. The surface area of the ball is 4\u03c0r<sup>2<\/sup>.<\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">The electric field coming out of the center of the sphere penetrates perpendicular to the surface of the sphere so that the formula of electric flux is \u03a6 = E A. The formula of the Gauss&#8217;s law is \u03a6 = Q\/\u03b5<sub>o <\/sub><\/span><!--more--><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">The electric field at a distance of r from the single charge is:<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-medium wp-image-4486\" src=\"https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/2018\/09\/Determining-the-electric-field-using-Gausss-law-2-131x300.png\" alt=\"Determining the electric field using Gauss's law 2\" width=\"131\" height=\"300\" srcset=\"https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/sites\/28\/2018\/09\/Determining-the-electric-field-using-Gausss-law-2-131x300.png 131w, https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/sites\/28\/2018\/09\/Determining-the-electric-field-using-Gausss-law-2.png 144w\" sizes=\"auto, (max-width: 131px) 100vw, 131px\" \/><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\"><i>E = electric field, k = Coulomb constant (9 x 10<\/i><sup><i>9<\/i><\/sup><i> N.m<\/i><sup><i>2<\/i><\/sup><i>\/C<\/i><sup><i>2<\/i><\/sup><i>), Q = electric charge, r = distance from the electric charge.<\/i><\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">This is the formula of the electric field produced by an electric charge. This formula can be derived using Coulomb&#8217;s law.<\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\"><b>Electric fields inside and outside the solid ball with homogeneous electricity charged <\/b><\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">A homogeneous positively charged solid ball has a total charge of Q, volume V = 4\/3 \u03c0 R<sup>3<\/sup> and the charge density in the solid ball is \u03c1 = Q\/V. Determine the electric field strength inside the ball and outside the ball.<\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\"><u>a) The electric field in the solid ball<\/u><\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\"><img loading=\"lazy\" decoding=\"async\" class=\"alignleft size-full wp-image-4487\" src=\"https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/2018\/09\/Determining-the-electric-field-using-Gausss-law-3.png\" alt=\"Determining the electric field using Gauss's law 3\" width=\"106\" height=\"107\" \/>The solid ball with the radius of R, while the selected Gauss surface is spherical with radius r, where r &lt; R. The volume of the solid ball is V and the volume of the Gauss sphere is V &#8216;.<\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">Electric charge in Gauss balls is:<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-4488\" src=\"https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/2018\/09\/Determining-the-electric-field-using-Gausss-law-4.png\" alt=\"Determining the electric field using Gauss's law 4\" width=\"238\" height=\"49\" \/><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">The electric field coming out of the center of the sphere penetrates perpendicular to the surface of the sphere so that the formula of electric flux is \u03a6 = E A. The formula for Gauss&#8217;s law is \u03a6 = Q\/\u03b5<sub>o<\/sub><\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">The electric field at the point with the distance of r from the center of the solid ball is:<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-medium wp-image-4489\" src=\"https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/2018\/09\/Determining-the-electric-field-using-Gausss-law-5-143x300.png\" alt=\"Determining the electric field using Gauss's law 5\" width=\"143\" height=\"300\" srcset=\"https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/sites\/28\/2018\/09\/Determining-the-electric-field-using-Gausss-law-5-143x300.png 143w, https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/sites\/28\/2018\/09\/Determining-the-electric-field-using-Gausss-law-5.png 161w\" sizes=\"auto, (max-width: 143px) 100vw, 143px\" \/><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">Based on the formula above, the electric field (E) is proportional to the electric charge (Q) and the radius of the Gauss surface (r), inversely proportional to the radius of the solid ball (R<sup>3<\/sup>)<\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\"><u>b) <\/u><span lang=\"en-US\"><u>Electric field outside the solid ball<\/u><\/span><\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\"><img loading=\"lazy\" decoding=\"async\" class=\"alignleft size-full wp-image-4490\" src=\"https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/2018\/09\/Determining-the-electric-field-using-Gausss-law-6.png\" alt=\"Determining the electric field using Gauss's law 6\" width=\"164\" height=\"168\" \/>A solid ball has the radius of R while the Gauss surface is spherical with radius r, where r &gt; R. The solid ball charge is Q; the solid ball is inside the gauss ball so that the electric charge in the gauss ball is Q.<\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">The electric field exits the center of the sphere and penetrates perpendicularly to the spherical surface so that the formula of electric flux is \u03a6 = E A. The formula of Gauss&#8217;s law is \u03a6 = Q\/\u03b5<sub>o<\/sub><\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">The electric field has the distance of r from the center of the solid ball is:<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-medium wp-image-4491\" src=\"https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/2018\/09\/Determining-the-electric-field-using-Gausss-law-7-127x300.png\" alt=\"Determining the electric field using Gauss's law 7\" width=\"127\" height=\"300\" srcset=\"https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/sites\/28\/2018\/09\/Determining-the-electric-field-using-Gausss-law-7-127x300.png 127w, https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/sites\/28\/2018\/09\/Determining-the-electric-field-using-Gausss-law-7.png 138w\" sizes=\"auto, (max-width: 127px) 100vw, 127px\" \/><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\"><b>The electric field inside and outside the hollow ball surface with the homogeneous electrically charged<\/b><\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">Hollow balls with the radius of R and volume V = 4\/3 \u03c0 R<sup>3<\/sup>, with homogeneous positively electrically charged on the surface with total charge Q. Determine the electric field strength inside and outside the surface of the sphere.<\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\"><u>a) <span lang=\"en-US\">The electric field in <\/span><span lang=\"en-US\">the <\/span><span lang=\"en-US\">hollow ball<\/span><\/u><\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">The ball is hollow, so the electrical charge is on the surface of the ball, while on the inside of the ball there is no electric charge. If the selected gauss surface is spherical and the gauss ball is inside the hollow ball, there is no electric charge inside the gauss ball. Electric charge is zero, so the electric field is also zero. So, the electric field inside the hollow ball is zero.<\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\"><u>b) <span lang=\"en-US\">Electric field outside the hollow ball<\/span><\/u><\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">The ball is hollow with the radius of R, while the selected Gauss surface is spherical with the radius of r, where r &gt; R.<\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">The electric field coming out of the center of the ball penetrates perpendicular to the surface of the sphere so that the formula of electric flux is \u03a6 = E A = E 4\u03c0 r<sup>2<\/sup>. The formula of Gauss&#8217;s law is \u03a6 = Q\/\u03b5<sub>o<\/sub>.<\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">The electric field at the point with the distance of r from the center of the hollow ball is:<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-4492\" src=\"https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/2018\/09\/Determining-the-electric-field-using-Gausss-law-8.png\" alt=\"Determining the electric field using Gauss's law 8\" width=\"137\" height=\"212\" \/><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\"><b>Electric fields near the electrically charged thin wires <\/b><\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">A thin wire has an infinite length, positively homogeneous electric charged with a charge density \u03bb. The electric charge on the wire is Q = \u03bb l. Determine the electric field strength around the thin wire.<\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\"><img loading=\"lazy\" decoding=\"async\" class=\"alignleft size-full wp-image-4493\" src=\"https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/2018\/09\/Determining-the-electric-field-using-Gausss-law-9.png\" alt=\"Determining the electric field using Gauss's law 9\" width=\"242\" height=\"141\" \/>Gauss surface is selected with the form of cylinders with length l and radius r. There are two forms of surfaces, a circular surface with radius r located at both cylindrical ends (the surface area is 2\u03c0r<sup>2<\/sup>) and a cylindrical surface with a length of l (the surface area is 2\u03c0r l).<\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">The electric charge is positive, and therefore the electric field exits the wire perpendicular to the surface of the tube <\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">so that the electric flux is \u03a6 = E A = E 2\u03c0r l. Instead, the electric field is parallel to the two ends of the circular tube so that the electric flux is zero.<\/span><\/span><\/p>\n<p class=\"western\" style=\"text-align: justify\" align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><span style=\"font-size: medium\">The electric field at a distance of r from the wire is:<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: times new roman, times, serif\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-4494\" src=\"https:\/\/gurumuda.net\/physics\/wp-content\/uploads\/2018\/09\/Determining-the-electric-field-using-Gausss-law-10.png\" alt=\"Determining the electric field using Gauss's law 10\" width=\"229\" height=\"265\" \/><\/span><\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"<p>Article about\u00a0Determining the electric field using Gauss law Electric field by a single point charge To calculate the electric field produced by a single positive charge, the first step is to select the spherical Gauss surface with radius r where the center of the sphere is at the single charge. The surface area of the &#8230; <a title=\"Determining the electric field using Gauss law\" class=\"read-more\" href=\"https:\/\/gurumuda.net\/physics\/determining-the-electric-field-using-gauss-law.htm\" aria-label=\"Read more about Determining the electric field using Gauss law\">Read more<\/a><\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_seopress_titles_title":"","_seopress_titles_desc":"Article about\u00a0Determining the electric field using Gauss law Electric field by a single point charge, The electric field inside and outside the hollow ball","_seopress_robots_index":"","_seopress_robots_follow":"","_seopress_robots_imageindex":"","_seopress_robots_snippet":"","_seopress_robots_primary_cat":"","_seopress_robots_breadcrumbs":"","_seopress_robots_freeze_modified_date":"","_seopress_robots_custom_modified_date":"","_seopress_robots_canonical":"","_seopress_social_fb_title":"","_seopress_social_fb_desc":"","_seopress_social_fb_img":"","_seopress_social_fb_img_attachment_id":0,"_seopress_social_fb_img_width":0,"_seopress_social_fb_img_height":0,"_seopress_social_twitter_title":"","_seopress_social_twitter_desc":"","_seopress_social_twitter_img":"","_seopress_social_twitter_img_attachment_id":0,"_seopress_social_twitter_img_width":0,"_seopress_social_twitter_img_height":0,"_seopress_redirections_value":"","_seopress_redirections_enabled":"","_seopress_redirections_enabled_regex":"","_seopress_redirections_logged_status":"","_seopress_redirections_param":"","_seopress_redirections_type":0,"_seopress_analysis_target_kw":"Determining the electric field using Gauss law","_seopress_news_disabled":"","_seopress_video_disabled":"","_seopress_video":[],"_seopress_pro_schemas_manual":[],"_seopress_pro_rich_snippets_disable_all":"","_seopress_pro_rich_snippets_disable":[],"_seopress_pro_schemas":[],"footnotes":""},"categories":[2],"tags":[],"class_list":["post-4484","post","type-post","status-publish","format-standard","hentry","category-basic-physics-tutorials"],"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/posts\/4484","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/comments?post=4484"}],"version-history":[{"count":0,"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/posts\/4484\/revisions"}],"wp:attachment":[{"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/media?parent=4484"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/categories?post=4484"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gurumuda.net\/physics\/wp-json\/wp\/v2\/tags?post=4484"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}