{"id":3994,"date":"2026-03-30T05:00:38","date_gmt":"2026-03-30T05:00:38","guid":{"rendered":"https:\/\/ksquareinstitute.in\/blog\/?p=3994"},"modified":"2026-04-03T12:26:01","modified_gmt":"2026-04-03T12:26:01","slug":"electromagnetic-waves-class-12-notes","status":"publish","type":"post","link":"https:\/\/ksquareinstitute.in\/blog\/electromagnetic-waves-class-12-notes\/","title":{"rendered":"Electromagnetic Waves Class 12 Notes: Ultimate Study Guide for NEET\/JEE"},"content":{"rendered":"\n<style>\n@import url('https:\/\/fonts.googleapis.com\/css2?family=DM+Sans:ital,wght@0,300;0,400;0,500;0,600;1,400&family=JetBrains+Mono:wght@400;500;700&family=Plus+Jakarta+Sans:wght@400;600;700;800&display=swap');\n\n:root {\n    --accent: #e8600a;\n    --accent-light: #fff3ec;\n    --accent-mid: #fde3cc;\n    --dark: #111827;\n    --text: #1a1a1a;\n    --text-muted: #4b5563;\n    --border: #e5e7eb;\n    --green-bg: #f0fdf4;\n    --green-border: #16a34a;\n    --blue-bg: #eff6ff;\n    --blue-border: #3b82f6;\n}\n\nbody {\n    font-family: 'DM Sans', sans-serif;\n    color: var(--text);\n    line-height: 1.7;\n    margin: 0;\n    padding: 0;\n    -webkit-font-smoothing: antialiased;\n}\n\nh2 {\n    font-family: 'Plus Jakarta Sans', sans-serif;\n    font-size: 22px;\n    font-weight: 700;\n    color: var(--dark);\n    margin: 0;\n    line-height: 1.3;\n}\n\nh3 {\n    font-family: 'Plus Jakarta Sans', sans-serif;\n    font-size: 18px;\n    font-weight: 700;\n    color: var(--dark);\n    margin: 24px 0 12px 0;\n}\n\n.content-padding {\n    padding: 0 0px;\n}\n\n@media (max-width: 768px) {\n    .content-padding { padding: 0 10px; 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color: var(--accent); text-decoration: none; font-weight: 600; font-size: 14px; margin-bottom: 6px; }\n\n.download-btn {\n    background: var(--dark);\n    color: white;\n    padding: 10px 20px;\n    border-radius: 8px;\n    text-decoration: none;\n    display: inline-flex;\n    align-items: center;\n    gap: 8px;\n    font-weight: 600;\n    font-size: 13px;\n    margin-top: 12px;\n}\n\n@media (max-width: 640px) {\n    .revision-list, .grid-cards { grid-template-columns: 1fr; }\n    .cta-buttons { flex-direction: column; }\n}\n<\/style>\n\n<div class=\"content-padding\">\n\n<div class=\"section-wrapper\">\n    <div class=\"badge\">01<\/div>\n    <h2>Introduction to Electromagnetic Waves class 12 notes<\/h2>\n<\/div>\n\n<p>For NEET aspirants, <strong>Electromagnetic Waves class 12 notes<\/strong> form a high-yield segment of Physics that bridges the gap between electricity and magnetism. Simply put, electromagnetic (EM) waves are waves consisting of oscillating electric and magnetic fields that are perpendicular to each other and also perpendicular to the direction of wave propagation. Unlike mechanical waves, these waves do not require a material medium to travel, meaning they can propagate through the absolute vacuum of space at the speed of light.<\/p>\n\n<div class=\"grid-cards\">\n    <div class=\"mini-card\">\n        <span class=\"card-title\">MAXWELL&#8217;S PREDICTION<\/span>\n        <p class=\"card-body\">James Clerk Maxwell mathematically predicted EM waves by identifying inconsistencies in existing laws of electromagnetism.<\/p>\n    <\/div>\n    <div class=\"mini-card\">\n        <span class=\"card-title\">HERTZ&#8217;S VERIFICATION<\/span>\n        <p class=\"card-body\">Heinrich Hertz experimentally proved the existence of these waves, confirming Maxwell&#8217;s revolutionary theory.<\/p>\n    <\/div>\n<\/div>\n\n<div class=\"section-wrapper\">\n    <div class=\"badge\">02<\/div>\n    <h2>Displacement Current: The Missing Link<\/h2>\n<\/div>\n\n<p>One of the most critical theoretical components in <strong>Electromagnetic Waves class 12 notes<\/strong> is the concept of Displacement Current. Maxwell noticed a limitation in Ampere\u2019s Circuital Law when applied to a charging capacitor. During the charging process, a magnetic field is observed between the plates, even though no actual conduction current flows through the gap.<\/p>\n\n<div class=\"formula-dark\">\n    <span class=\"formula-label\">DISPLACEMENT CURRENT FORMULA<\/span>\n    <p class=\"formula-text-orange\">I<sub>d<\/sub> = \u03b5<sub>0<\/sub> (d\u03a6<sub>E<\/sub> \/ dt)<\/p>\n<\/div>\n\n<p>This &#8220;current&#8221; is not due to the flow of charges but is produced by a <strong>changing electric field<\/strong>. Maxwell modified Ampere\u2019s Law to include this term, resulting in the Ampere-Maxwell Law.<\/p>\n\n<div class=\"callout tip\">\n    <div class=\"pill pill-tip\">TIP<\/div>\n    <div>In a steady-state DC circuit, I<sub>d<\/sub> is zero. It only exists when the electric flux is changing with time, such as during the charging or discharging of a capacitor.<\/div>\n<\/div>\n\n<a href=\"https:\/\/courses.ksquare.co.in\/new-courses\/3-mission-180-neet-physics-rankers-batch\" target=\"_blank\" rel=\"nofollow noopener noreferrer\" style=\"display:block; margin-bottom:20px;\">\n  <img decoding=\"async\" src=\"https:\/\/ksquareinstitute.in\/blog\/wp-content\/uploads\/2026\/03\/Course-Poromo-Banner-scaled.png\" alt=\"Mission 180 NEET Physics Rankers Batch - KSquare Career Institute\" style=\"width:100%; height:auto; border-radius:10px; display:block;\">\n<\/a>\n\n<div class=\"section-wrapper\">\n    <div class=\"badge\">03<\/div>\n    <h2>Maxwell\u2019s Equations in Electromagnetic Waves<\/h2>\n<\/div>\n\n<p>To master <strong>Electromagnetic Waves class 12 notes<\/strong>, you must understand the four fundamental equations that describe all classical electromagnetic phenomena:<\/p>\n\n<table>\n    <thead>\n        <tr>\n            <th>Equation Name<\/th>\n            <th>Physical Meaning<\/th>\n            <th>Mathematical Essence<\/th>\n        <\/tr>\n    <\/thead>\n    <tbody>\n        <tr>\n            <td>Gauss\u2019s Law (Electrostatics)<\/td>\n            <td>Electric flux depends on enclosed charge<\/td>\n            <td>Total flux = q \/ \u03b5<sub>0<\/sub><\/td>\n        <\/tr>\n        <tr>\n            <td>Gauss\u2019s Law (Magnetism)<\/td>\n            <td>No magnetic monopoles exist<\/td>\n            <td>Magnetic flux through closed surface = 0<\/td>\n        <\/tr>\n        <tr>\n            <td>Faraday\u2019s Law<\/td>\n            <td>Changing magnetic field produces electric field<\/td>\n            <td>EMF = -d\u03a6<sub>B<\/sub> \/ dt<\/td>\n        <\/tr>\n        <tr>\n            <td>Ampere-Maxwell Law<\/td>\n            <td>Magnetic field due to current + displacement current<\/td>\n            <td>B depends on I<sub>c<\/sub> and I<sub>d<\/sub><\/td>\n        <\/tr>\n    <\/tbody>\n<\/table>\n\n<div class=\"section-wrapper\">\n    <div class=\"badge\">04<\/div>\n    <h2>Nature of Electromagnetic Waves<\/h2>\n<\/div>\n\n<p>The <strong>transverse nature<\/strong> of EM waves is a recurring theme in NEET exams. This means that the oscillation of the Electric Field (E) and Magnetic Field (B) occurs in directions perpendicular to the direction of wave propagation.<\/p>\n\n<div class=\"grid-cards\">\n    <div class=\"mini-card\">\n        <span class=\"card-title\">PHASE RELATIONSHIP<\/span>\n        <p class=\"card-body\">Electric and magnetic fields in an EM wave oscillate in phase, reaching their maxima and minima simultaneously.<\/p>\n    <\/div>\n    <div class=\"mini-card\">\n        <span class=\"card-title\">DIRECTION OF PROPAGATION<\/span>\n        <p class=\"card-body\">The direction is given by the cross product of the fields: E \u00d7 B.<\/p>\n    <\/div>\n<\/div>\n\n<div class=\"section-wrapper\">\n    <div class=\"badge\">05<\/div>\n    <h2>Characteristics and Speed of EM Waves<\/h2>\n<\/div>\n\n<p>Electromagnetic waves carry both energy and momentum. When they strike a surface, they exert a pressure known as <strong>radiation pressure<\/strong>. In a vacuum, all EM waves travel at the same constant speed, regardless of their wavelength.<\/p>\n\n<div class=\"formula-orange\">\n    <span class=\"formula-label\">SPEED OF LIGHT FORMULA<\/span>\n    <p class=\"formula-text-dark\">c = 1 \/ \u221a(\u03bc<sub>0<\/sub>\u03b5<sub>0<\/sub>) \u2248 3 \u00d7 10<sup>8<\/sup> m\/s<\/p>\n    <p class=\"formula-text-dark\">c = E<sub>0<\/sub> \/ B<sub>0<\/sub><\/p>\n<\/div>\n\n<div class=\"section-wrapper\">\n    <div class=\"badge\">06<\/div>\n    <h2>Energy and Momentum Transfer<\/h2>\n<\/div>\n\n<p>Since EM waves consist of fields, they store energy. The total energy density is the sum of electric and magnetic energy densities. For a wave traveling in space, the average energy density is equally shared between the two fields.<\/p>\n\n<div class=\"formula-dark\">\n    <span class=\"formula-label\">POYNTING VECTOR (S)<\/span>\n    <p class=\"formula-text-orange\">S = (1 \/ \u03bc<sub>0<\/sub>) (E \u00d7 B)<\/p>\n<\/div>\n\n<div class=\"callout warning\">\n    <div class=\"pill pill-warning\">WARN<\/div>\n    <div>Don&#8217;t forget that if an EM wave is completely absorbed by a surface, the momentum delivered is p = U\/c. If it is reflected, the momentum delivered is p = 2U\/c.<\/div>\n<\/div>\n\n<div class=\"section-wrapper\">\n    <div class=\"badge\">07<\/div>\n    <h2>The Electromagnetic Spectrum Overview<\/h2>\n<\/div>\n\n<p>The electromagnetic spectrum is an orderly classification of EM waves according to their frequency or wavelength. In your <strong>Electromagnetic Waves class 12 notes<\/strong>, memorizing the order and specific uses of each region is vital for scoring easy marks in NEET.<\/p>\n\n<table>\n    <thead>\n        <tr>\n            <th>Region<\/th>\n            <th>Wavelength Range<\/th>\n            <th>Typical Source<\/th>\n        <\/tr>\n    <\/thead>\n    <tbody>\n        <tr>\n            <td>Radio Waves<\/td>\n            <td>> 0.1 m<\/td>\n            <td>Rapid acceleration of electrons in aerials<\/td>\n        <\/tr>\n        <tr>\n            <td>Microwaves<\/td>\n            <td>0.1 m to 1 mm<\/td>\n            <td>Klystron or Magnetron valves<\/td>\n        <\/tr>\n        <tr>\n            <td>Infrared<\/td>\n            <td>1 mm to 700 nm<\/td>\n            <td>Hot bodies and molecules<\/td>\n        <\/tr>\n        <tr>\n            <td>Visible Light<\/td>\n            <td>700 nm to 400 nm<\/td>\n            <td>Electrons in atoms emitting light<\/td>\n        <\/tr>\n        <tr>\n            <td>Ultraviolet<\/td>\n            <td>400 nm to 1 nm<\/td>\n            <td>Inner shell electrons, Sun<\/td>\n        <\/tr>\n        <tr>\n            <td>X-Rays<\/td>\n            <td>1 nm to 10<sup>-3<\/sup> nm<\/td>\n            <td>Bombarding metal with high energy electrons<\/td>\n        <\/tr>\n        <tr>\n            <td>Gamma Rays<\/td>\n            <td>< 10<sup>-3<\/sup> nm<\/td>\n            <td>Radioactive decay of nuclei<\/td>\n        <\/tr>\n    <\/tbody>\n<\/table>\n\n<a href=\"https:\/\/ksquareinstitute.in\/neet-2026-rank-predictor\/\" target=\"_blank\" rel=\"nofollow noopener noreferrer\" style=\"display:block; margin-bottom:20px;\">\n  <img decoding=\"async\" src=\"https:\/\/ksquareinstitute.in\/blog\/wp-content\/uploads\/2026\/03\/neet-2026-college-and-rank-predictor-scaled.png\" alt=\"NEET 2026 Rank Predictor - KSquare Career Institute\" style=\"width:100%; height:auto; border-radius:10px; display:block;\">\n<\/a>\n\n<div class=\"section-wrapper\">\n    <div class=\"badge\">08<\/div>\n    <h2>Properties and Applications of Spectrum Regions<\/h2>\n<\/div>\n\n<p>Understanding the application of each wave type helps in solving conceptual questions in the NEET Physics section.<\/p>\n\n<div class=\"grid-cards\">\n    <div class=\"mini-card\">\n        <span class=\"card-title\">RADIO &#038; MICROWAVES<\/span>\n        <p class=\"card-body\">Radio waves are used in cellular communication. Microwaves are ideal for RADAR and domestic cooking due to their frequency matching water resonance.<\/p>\n    <\/div>\n    <div class=\"mini-card\">\n        <span class=\"card-title\">INFRARED &#038; UV<\/span>\n        <p class=\"card-body\">Infrared (heat waves) is used in remote controls and physical therapy. UV rays are used in water purification and LASIK eye surgery.<\/p>\n    <\/div>\n<\/div>\n\n<div class=\"section-wrapper\">\n    <div class=\"badge\">09<\/div>\n    <h2>Wave Speed, Frequency, and Wavelength Relation<\/h2>\n<\/div>\n\n<p>The universal wave equation applies to all parts of the EM spectrum. This is the foundation for most numerical problems in <strong>Electromagnetic Waves class 12 notes<\/strong>.<\/p>\n\n<div class=\"formula-orange\">\n    <span class=\"formula-label\">WAVE RELATION<\/span>\n    <p class=\"formula-text-dark\">c = \u03bd\u03bb<\/p>\n    <p class=\"formula-text-dark\">\u03bd = c \/ \u03bb<\/p>\n<\/div>\n\n<div class=\"section-wrapper\">\n    <div class=\"badge\">10<\/div>\n    <h2>Important Concepts for NEET Exams<\/h2>\n<\/div>\n\n<p>Focus your revision on these high-probability topics:<\/p>\n<ul>\n    <li>The theoretical significance of Displacement Current.<\/li>\n    <li>The phase relationship between E and B fields (always in phase).<\/li>\n    <li>The transverse nature and how to find propagation direction using E \u00d7 B.<\/li>\n    <li>Identifying the EM region based on given wavelength or frequency.<\/li>\n<\/ul>\n\n<div class=\"section-wrapper\">\n    <div class=\"badge\">11<\/div>\n    <h2>Graphical and Conceptual Understanding<\/h2>\n<\/div>\n\n<p>Visualizing an EM wave is key. Imagine the E-field oscillating along the Y-axis and the B-field along the Z-axis; the wave then propagates along the X-axis. This 3D orientation is essential for solving direction-based cross-product problems.<\/p>\n\n<div class=\"section-wrapper\">\n    <div class=\"badge\">12<\/div>\n    <h2>Numericals and Problem Types<\/h2>\n<\/div>\n\n<p>Numerical questions typically fall into three categories:<\/p>\n<ol>\n    <li><strong>Formula-Based:<\/strong> Calculating frequency from wavelength or finding the amplitude of B<sub>0<\/sub> given E<sub>0<\/sub>.<\/li>\n    <li><strong>Spectrum-Based:<\/strong> Identifying the type of radiation used in a specific medical or technical application.<\/li>\n    <li><strong>Conceptual:<\/strong> Predicting the effect of changing medium on wave speed (v = c\/n).<\/li>\n<\/ol>\n\n<div class=\"section-wrapper\">\n    <div class=\"badge\">13<\/div>\n    <h2>Common Mistakes to Avoid<\/h2>\n<\/div>\n\n<div class=\"callout warning\">\n    <div class=\"pill pill-warning\">WARN<\/div>\n    <div>Avoid these pitfalls:\n        <br>1. Thinking EM waves are longitudinal (they are always transverse).\n        <br>2. Confusing EM waves with sound waves (sound requires a medium).\n        <br>3. Mixing up the order of the spectrum (Radio has longest \u03bb, Gamma has highest \u03bd).\n    <\/div>\n<\/div>\n\n<div class=\"section-wrapper\">\n    <div class=\"badge\">14<\/div>\n    <h2>Exam Strategy for Electromagnetic Waves<\/h2>\n<\/div>\n\n<p>To score full marks, prioritize theory and the EM spectrum chart. Since the chapter is relatively short, it offers a high return on investment. Regularly practice identifying wavelengths and converting units (Angstroms to meters).<\/p>\n\n<div class=\"revision-box\">\n    <h3>Quick Revision Summary: Electromagnetic Waves<\/h3>\n    <ul class=\"revision-list\">\n        <li>Displacement current I<sub>d<\/sub> = \u03b5<sub>0<\/sub> d\u03a6<sub>E<\/sub>\/dt<\/li>\n        <li>EM waves are transverse in nature<\/li>\n        <li>Speed in vacuum c = 3 \u00d7 10<sup>8<\/sup> m\/s<\/li>\n        <li>E\/B = c (Relation between amplitudes)<\/li>\n        <li>Energy is shared equally between E and B fields<\/li>\n        <li>Intensity I = U<sub>avg<\/sub> \u00d7 c<\/li>\n        <li>Spectrum order: R-M-I-V-U-X-G<\/li>\n        <li>Poynting vector S represents energy flux<\/li>\n        <li>EM waves exert radiation pressure<\/li>\n        <li>\u03b3-rays have the highest frequency and energy<\/li>\n        <li>Radio waves have the longest wavelength<\/li>\n        <li>Velocity in medium v = 1 \/ \u221a(\u03bc\u03b5)<\/li>\n    <\/ul>\n    <a href=\"#\" rel=\"nofollow noopener noreferrer\" class=\"download-btn\">\n        Download Summary Sheet\n    <\/a>\n<\/div>\n\n<div class=\"section-wrapper\">\n    <div class=\"badge\">15<\/div>\n    <h2>FAQs: Electromagnetic Waves<\/h2>\n<\/div>\n\n<details>\n    <summary>What is the source of an electromagnetic wave?<\/summary>\n    <div class=\"faq-answer\">\n        An accelerating or oscillating charge is the primary source of electromagnetic waves. A charge at rest produces only an electric field, and a charge moving with constant velocity produces both fields but no waves.\n    <\/div>\n<\/details>\n\n<details>\n    <summary>Do EM waves carry momentum?<\/summary>\n    <div class=\"faq-answer\">\n        Yes, EM waves carry linear momentum. When they strike a surface, they transfer this momentum, exerting radiation pressure.\n    <\/div>\n<\/details>\n\n<details>\n    <summary>Which part of the EM spectrum is used for satellite communication?<\/summary>\n    <div class=\"faq-answer\">\n        Microwaves are primarily used for satellite communication because they can penetrate the Earth&#8217;s ionosphere without significant reflection or absorption.\n    <\/div>\n<\/details>\n\n<details>\n    <summary>Are electric and magnetic fields perpendicular in EM waves?<\/summary>\n    <div class=\"faq-answer\">\n        Yes, the electric field vector, magnetic field vector, and the direction of propagation are all mutually perpendicular to each other.\n    <\/div>\n<\/details>\n\n<details>\n    <summary>What is the velocity of EM waves in a medium of refractive index &#8216;n&#8217;?<\/summary>\n    <div class=\"faq-answer\">\n        The velocity in a medium is given by v = c \/ n, where c is the speed of light in a vacuum.\n    <\/div>\n<\/details>\n\n<div class=\"internal-links\">\n    <h4>Must-Read for NEET 2026<\/h4>\n    <a href=\"https:\/\/ksquareinstitute.in\/blog\/neet-physics-survival-kit-2026\/\">NEET Physics Survival Kit 2026<\/a>\n    <a href=\"https:\/\/ksquareinstitute.in\/blog\/organic-chemistry-strategy-neet\/\">Organic Chemistry Strategy<\/a>\n    <a href=\"https:\/\/ksquareinstitute.in\/blog\/neet-biology-tricks-for-exams\/\">NEET Biology Tricks<\/a>\n    <a href=\"https:\/\/ksquareinstitute.in\/blog\/score-340-in-neet-biology\/\">How to Score 340+ in Biology<\/a>\n    <a href=\"https:\/\/ksquareinstitute.in\/blog\/top-10-tricky-neet-biology-diagrams\/\">Tricky Biology Diagrams Guide<\/a>\n<\/div>\n\n<\/div>\n\n<section class=\"cta-section\">\n    <h2>Boost Your NEET Rank with KSquare<\/h2>\n    <p>Get exclusive access to the Mission 180 Physics Rankers Batch and master Electromagnetic Waves with expert guidance and high-yield notes.<\/p>\n    <div class=\"cta-buttons\">\n        <a href=\"https:\/\/courses.ksquare.co.in\/new-courses\/3-mission-180-neet-physics-rankers-batch\" target=\"_blank\" rel=\"nofollow noopener noreferrer\" class=\"btn btn-white\">Join the Batch<\/a>\n        <a href=\"https:\/\/ksquareinstitute.in\/free-study-material\/\" target=\"_blank\" rel=\"nofollow noopener noreferrer\" class=\"btn btn-outline\">Free Study Material<\/a>\n    <\/div>\n<\/section>\n\n\n\n<!DOCTYPE html>\n<html lang=\"en\">\n<head>\n  <meta charset=\"UTF-8\">\n  <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\">\n  <title>Table of Contents \u2014 Physics Class 12<\/title>\n  \n  <!-- Google Fonts Import -->\n  <link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\n  <link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin>\n  <link href=\"https:\/\/fonts.googleapis.com\/css2?family=DM+Sans:ital,opsz,wght@0,9..40,100..1000;1,9..40,100..1000&#038;family=Plus+Jakarta+Sans:ital,wght@0,200..800;1,200..800&#038;display=swap\" rel=\"stylesheet\">\n  \n  <style>\n    \/* Scoped wrapper using a unique ID to prevent CSS conflicts. *\/\n    #physics-toc-wrapper {\n      font-family: 'DM Sans', sans-serif;\n      width: 100%;\n      margin: 0;\n      padding: 60px 0;\n      color: #111;\n      background: #fff;\n      -webkit-font-smoothing: antialiased;\n    }\n\n    #physics-toc-wrapper .container-inner {\n      width: 100%;\n      margin: 0 auto;\n      padding: 0; \/* No left\/right padding for edge-to-edge look *\/\n    }\n\n    #physics-toc-wrapper h1 {\n      font-family: 'Plus Jakarta Sans', sans-serif;\n      font-size: 0.85rem;\n      font-weight: 700;\n      color: #71717a;\n      margin: 0 0 8px;\n      letter-spacing: 0.1em;\n      text-transform: uppercase;\n      padding-left: 16px; \n    }\n\n    #physics-toc-wrapper h2 {\n      font-family: 'Plus Jakarta Sans', sans-serif;\n      font-size: 2.25rem;\n      font-weight: 800;\n      margin: 0 0 48px;\n      letter-spacing: -0.02em;\n      color: #09090b;\n      padding-left: 16px;\n    }\n\n    #physics-toc-wrapper table {\n      width: 100%;\n      border-collapse: collapse;\n      border-spacing: 0;\n      border-top: 1px solid #e4e4e7;\n      border-bottom: 1px solid #e4e4e7;\n    }\n\n    #physics-toc-wrapper tr {\n      border-bottom: 1px solid #e4e4e7;\n      transition: all 0.2s ease;\n    }\n\n    #physics-toc-wrapper tr:hover {\n      background-color: #f8fafc;\n    }\n\n    #physics-toc-wrapper tr:last-child {\n      border-bottom: none;\n    }\n\n    #physics-toc-wrapper td {\n      padding: 24px 16px;\n      vertical-align: middle;\n      font-size: 1.05rem;\n      font-weight: 500;\n      border-right: 1px solid #e4e4e7;\n    }\n\n    #physics-toc-wrapper td:last-child {\n      border-right: none;\n    }\n\n    \/* First column (Numbers) alignment and padding *\/\n    #physics-toc-wrapper td:first-child {\n      color: #a1a1aa;\n      font-size: 0.9rem;\n      width: 70px;\n      font-weight: 400;\n      font-variant-numeric: tabular-nums;\n      text-align: center;\n      padding-left: 10px;\n    }\n\n    \/* Middle column (Chapter Name) alignment and padding *\/\n    #physics-toc-wrapper td:nth-child(2) {\n      padding-left: 24px;\n      color: #18181b;\n    }\n\n    \/* Last column (Button) alignment and padding *\/\n    #physics-toc-wrapper td:last-child {\n      text-align: right;\n      width: 180px;\n      padding-right: 16px;\n    }\n\n    \/* Button Styling *\/\n    #physics-toc-wrapper a.go {\n      display: inline-block;\n      font-family: 'Plus Jakarta Sans', sans-serif;\n      font-size: 0.75rem;\n      font-weight: 800;\n      padding: 12px 24px;\n      border: 1.5px solid #18181b;\n      border-radius: 8px;\n      color: #18181b;\n      text-decoration: none;\n      letter-spacing: 0.05em;\n      text-transform: uppercase;\n      transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);\n      white-space: nowrap;\n    }\n\n    #physics-toc-wrapper a.go:hover {\n      background: #18181b;\n      color: #ffffff;\n      transform: translateY(-2px);\n      box-shadow: 0 4px 12px rgba(24, 24, 27, 0.15);\n    }\n\n    \/* Responsive adjustments *\/\n    @media (max-width: 768px) {\n      #physics-toc-wrapper h2 {\n        font-size: 1.75rem;\n        margin-bottom: 32px;\n      }\n      #physics-toc-wrapper td {\n        padding: 18px 12px;\n        font-size: 0.95rem;\n      }\n    }\n  <\/style>\n<\/head>\n<body>\n\n<div id=\"physics-toc-wrapper\">\n  <div class=\"container-inner\">\n    <h1>Table of Contents<\/h1>\n    <h2>Physics &mdash; Class 12<\/h2>\n    \n    <table>\n      <tr><td>01<\/td><td>Electric Charges and Fields<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/electric-charges-and-fields-class-12-notes-pdf\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>02<\/td><td>Electrostatic Potential and Capacitance<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/electrostatic-potential-and-capacitance-notes-class-12\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>03<\/td><td>Current Electricity<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/current-electricity-class-12-notes-pdf\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>04<\/td><td>Moving Charges and Magnetism<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/moving-charges-and-magnetism-class-12-notes\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>05<\/td><td>Magnetism and Matter<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/magnetism-and-matter-class-12-notes-pdf\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>06<\/td><td>Electromagnetic Induction<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/electromagnetic-induction-class-12-notes\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>07<\/td><td>Alternating Current<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/alternating-current-class-12-notes\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>08<\/td><td>Electromagnetic Waves<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/electromagnetic-waves-class-12-notes\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>09<\/td><td>Ray Optics and Optical Instruments<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/ray-optics-and-optical-instruments-class-12\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>10<\/td><td>Wave Optics<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/wave-optics-class-12-notes-pdf\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>11<\/td><td>Dual Nature of Radiation and Matter<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/dual-nature-of-radiation-and-matter-class-12\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>12<\/td><td>Atoms<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/atoms-class-12-notes\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>13<\/td><td>Nuclei<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/nuclei-class-12-notes\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>14<\/td><td>Semiconductor Electronics<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/semiconductor-electronics-class-12-notes\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n    <\/table>\n  <\/div>\n<\/div>\n\n<\/body>\n<\/html>\n","protected":false},"excerpt":{"rendered":"<p>01 Introduction to Electromagnetic Waves class 12 notes For NEET aspirants, Electromagnetic Waves class 12 notes form a high-yield segment of Physics that bridges the gap between electricity and magnetism. Simply put, electromagnetic (EM) waves are waves consisting of oscillating electric and magnetic fields that are perpendicular to each other and also perpendicular to the [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[127],"tags":[237,234,231,233,239,238,235,232,240,236],"class_list":["post-3994","post","type-post","status-publish","format-standard","hentry","category-free-study-material","tag-cbse-class-12-physics-electromagnetic-waves","tag-displacement-current-class-12","tag-electromagnetic-spectrum-class-12","tag-electromagnetic-waves-class-12-notes","tag-em-spectrum-order","tag-em-wave-numericals-class-12","tag-em-waves-class-12-physics-notes","tag-maxwell-equations-class-12","tag-poynting-vector-class-12","tag-properties-of-electromagnetic-waves"],"blocksy_meta":{"page_structure_type":"type-1","styles_descriptor":{"styles":{"desktop":"","tablet":"","mobile":""},"google_fonts":[],"version":6}},"_links":{"self":[{"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts\/3994","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/comments?post=3994"}],"version-history":[{"count":2,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts\/3994\/revisions"}],"predecessor-version":[{"id":4225,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts\/3994\/revisions\/4225"}],"wp:attachment":[{"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/media?parent=3994"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/categories?post=3994"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/tags?post=3994"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}