Difference between Electric Field and Magnetic Field

DifferencesDigital ElectronicsElectronics & Electrical

<p>There is a property of space which is caused by the motion of the electric charge, is known as <strong>electromagnetic field</strong>. There are two component of an electromagnetic field viz. −</p><ul class="list"><li><p>Electric field</p></li><li><p>Magnetic field</p></li></ul><p>A stationary electric charge produces only an electric field in the surrounding space. If the electric charge is moving, then it also produces a magnetic field. The electric field and magnetic field occupy different planes relative to the cause of the electromagnetic field, i.e., moving charge.</p><p>Therefore, one of the major difference between electric field and the magnetic field is that the electric field produces around a static electric charge while the magnetic field produces around the moving charge (or poles of a magnet also).</p><p>Many other differences between magnetic field and electric field are highlighted in the table below. We have also added a short description of the electric field and magnetic field for your reference, which helps you to understand the differences between them.</p><h2>What is an Electric Field?</h2><p>The physical field around the electrically charged particles in which all other electric charges experiences a force of either attraction or repulsion is known as <strong>electric field</strong>. The electric field is produced from electric charges or from time-varying magnetic fields. The measure of electric field around a charge is termed as electric field intensity, denoted by ‘<strong>E</strong>’. The electric field is a vector quantity because it has both magnitude and direction.</p><p><img src="https://www.tutorialspoint.com/assets/questions/tmp/Electric field.png" class="fr-fic fr-dib" width="700" height="200"></p><p>The behavior of electric field is described by the Gauss’s law and Faraday’s law of induction. Mathematically, the electric field can be defined as the electric force per unit charge, i.e.</p><p>$$\mathrm{\mathit{E\, \mathrm{=}\, \frac{F}{Q}}}$$</p><p>The intensity of electric field is measured in <strong>Newton per coulomb</strong>. The direction of the electric field is taken as the direction of the force which is exerted on a positive electric charge. The electric field around an electric charge is represented by imaginary field lines. The electric field lines show that the electric field is radially outwards from a positive charge and radially inwards a negative charge.</p><h2>What is Magnetic Field?</h2><p>The space around a magnet where its poles exhibit a force of either attraction or repulsion is known as <strong>magnetic field</strong>. When the electric charges move in space or through a conductor, they also produce magnetic field.</p><p><img src="https://www.tutorialspoint.com/assets/questions/tmp/Magnetic field field.png" class="fr-fic fr-dib" width="700" height="210"></p><p>Therefore, a magnet and moving electric charge produce magnetic field around them, which is represented by imaginary lines called <strong>magnetic field lines</strong>. As the magnetic field has magnitude and direction, thus it is also a vector quantity. The measure of magnetic field is termed as <strong>magnetic field strength</strong>, denoted by ‘<strong>H</strong>’. But, mathematically, the magnetic field is measured in terms of magnetic flux density, denoted by <strong>B</strong> and is given by,</p><p>$$\mathrm{\mathit{B\, \mathrm{=}\, \frac{\phi }{A}}}$$</p><p>The unit of magnetic flux density is <strong>Tesla</strong> or <strong>Weber/m<sup>2</sup></strong>. The direction of the magnetic field outside the magnet is from north pole to south poles and inside the magnetic, it is from south pole to north pole.</p><h2>Difference between Electric and Magnetic Field</h2><p>The following table highlights the key differences between an electric field and a magnetic field −</p><table class="table table-bordered"><thead><tr><th style="text-align: center;">Parameter</th><th style="text-align: center;">Electric Field</th><th style="text-align: center;">Magnetic Field</th></tr></thead><tbody><tr><td style="vertical-align: middle; text-align: center;">Definition</td><td>The region around an electrically charged particle where all other charges experience a force of attraction or repulsion is known as electric field.</td><td>The magnetic field is the region around a magnet in which its poles exhibit a force of attraction or repulsion.</td></tr><tr><td style="vertical-align: middle; text-align: center;">Measure</td><td>The measure of electric field is known as electric field strength or electric field intensity.</td><td>The measure of magnetic field is called magnetic field intensity or magnetic field strength.</td></tr><tr><td style="vertical-align: middle; text-align: center;">Denotation</td><td>The electric field is denoted by ‘<strong>E</strong>’.</td><td>Magnetic field is denoted by ‘<strong>B</strong>’.</td></tr><tr><td style="vertical-align: middle; text-align: center;">Expression</td><td>The intensity of electric field is given by,$\mathrm{\mathit{E\, \mathrm{=}\, \frac{F}{Q}}}$<br></td><td>The magnetic field (or magnetic flux density) is given by,$\mathrm{\mathit{B\, \mathrm{=}\, \frac{\phi }{A}}}$<br></td></tr><tr><td style="vertical-align: middle; text-align: center;">Unit of measurement</td><td>The measuring unit of electric field is Newton per coulomb or volt per meter.</td><td>The unit of magnetic field (i.e. magnetic flux density) is Tesla or weber per sq. meter.</td></tr><tr><td style="vertical-align: middle; text-align: center;">Cause of production</td><td>Electric field is caused by electric charge, may be static or moving.</td><td>Magnetic field is produced by magnet or moving charge.</td></tr><tr><td style="vertical-align: middle; text-align: center;">Direction of field lines</td><td>The electric field lines start from a positive charge and end on a negative charge.</td><td>The magnetic field lines move from north pole to south pole outside the magnet, and move from south pole to north pole inside the magnet.</td></tr><tr><td style="vertical-align: middle; text-align: center;">Formation of loop</td><td>The electric field lines do not form a closed loop.</td><td>Magnetic field lines form a closed loop.</td></tr><tr><td style="vertical-align: middle; text-align: center;">Measuring instrument</td><td>In order to measure the strength of electric field the Electrometer is used.</td><td>Magnetometer is used to measure the strength of magnetic field.</td></tr><tr><td style="vertical-align: middle; text-align: center;">Movement in electromagnetic field</td><td>The electric field is perpendicular to the magnetic field.</td><td>The magnetic field is perpendicular to the electric field.</td></tr><tr><td style="vertical-align: middle; text-align: center;">Force</td><td>The force produced by electric field on the charges is directly proportional to electric charge.</td><td>Force produced by a magnetic field is directly proportional to strength of the magnetic pole (in case of magnet) or to charge and speed of the electric charge (in case electromagnetism).</td></tr><tr><td style="vertical-align: middle; text-align: center;">Reactive power (in VAr)</td><td>The electric field produces the reactive power as in a capacitor.</td><td>Magnetic field absorbs the reactive power as in an inductor.</td></tr><tr><td style="vertical-align: middle; text-align: center;">Pole</td><td>Electric field may have monopole (due to one charge) or dipole (due to two charges).</td><td>Magnetic field always have dipole. Single pole of magnet cannot exist.</td></tr><tr><td style="vertical-align: middle; text-align: center;">Dimensions</td><td>An electric field exists in two dimensions.</td><td>A magnetic field exists in three dimensions.</td></tr><tr><td style="vertical-align: middle; text-align: center;">Work done on a particle</td><td>When a charged particle enters an electric field, the electric field can influence the particle by changing velocity or direction or both, i.e. the electric field can do work on a particle.</td><td>A magnetic field cannot do any work on a particle. When a particle enters into a magnetic field, the magnetic field cannot influence the particle by changing its velocity or direction.</td></tr></tbody></table><h2>Conclusion</h2><p>From the above discussion, we can conclude that both magnetic fields and electric fields are vector quantities having magnitude as well as direction. In this article, we highlighted the key features of an electric field and how it differs from a magnetic field.</p>
Updated on 28-Jun-2022 08:03:02