This document provides an overview of the topic "Electromagnetism" presented by Biniwale Suraj for the 1st year B.E. (C) class at GEC Dahod Mechanical Dept. It covers the following key points in electromagnetism:
1. It introduces electromagnetism and discusses its importance in electrical devices.
2. It reviews the history of discoveries in electromagnetism and Maxwell's unification of electricity and magnetism.
3. It explains electromagnetic concepts such as the magnetic field produced by electric current, Faraday's laws of induction, and induced electromotive force.
4. It also discusses magnetic effects such as the direction
The document discusses how electromagnetic induction works to generate electricity using magnets and coils of wire. It explains that changing magnetic fields can induce currents in conductors and that this principle is used in electrical generators. It also describes how transformers work to change voltage levels, using step-up transformers to increase voltage for long-distance transmission and step-down transformers to decrease voltage for safe household use.
This document describes principles of electromagnetic induction and various experiments conducted by Michael Faraday. It explains Faraday's law of induction and Lenz's law. It then discusses the working principles of AC generators and transformers. AC generators produce alternating current using a coil rotating in a magnetic field with slip rings. Transformers use the principle of electromagnetic induction to change voltage levels using a primary and secondary coil around an iron core, with different turn ratios determining voltage increase or decrease.
As electric field, that is, force per unit charge is a vector quantity; it can be used to represent overall effect of electric field in system of electric charges. Similarly electric field can be used in pictorial form to describe the overall intensity of the field. Copy the link given below and paste it in new browser window to get more information on Electric Field Lines www.askiitians.com/iit-jee-electrostatics/electric-field-lines/
This document provides an introduction to electromagnetism. It discusses how electricity and magnetism are different facets of the same electromagnetic force. It covers the history of electromagnetism from ancient observations of amber and lodestone to Maxwell's equations unifying electricity and magnetism. The document also describes magnetic fields and forces, electromagnetic induction, electromagnets, Tesla coils, the electromagnetic spectrum, and potential health effects of low-frequency electromagnetic fields.
The document is a presentation about magnetic fields and field lines. It defines magnetic field as the space around a magnet where magnetic force can be felt. It describes how to locate magnetic fields using iron filings or a compass, and defines magnetic field lines as the paths that an independent north pole would take in a magnetic field. It discusses the properties of strong and weak magnetic fields based on the closeness of field lines, and types of magnetic fields such as uniform and non-uniform. Key properties of magnetic field lines are that they are continuous closed curves, give the direction of the magnetic field, and do not intersect.
Magnetism is produced by magnets which have north and south poles and magnetic field lines. The earliest magnets were naturally occurring lodestone. Magnets attract opposite poles and repel like poles. The Earth itself acts like a giant bar magnet due to its nickel-iron core. Magnetic substances are composed of small magnetic domains that align when exposed to an external magnetic field. Electricity and magnetism are related because electric currents produce magnetic fields. Electromagnets are coils of wire that produce strong magnetic fields when electric current passes through. Galvanometers use electromagnets to measure electric current. Electric motors convert electric current into rotational motion using electromagnetic induction. Generators also use electromagnetic induction to produce electric current from mechanical motion. Direct
The document discusses electricity and magnetism. It explains that electric charges create electric fields and moving charges experience magnetic forces. Charges and electric currents produce both electric and magnetic fields, known as electromagnetic fields. Permanent magnets have their own magnetic fields, and magnetism is the properties and interactions of magnets. Electromagnets are magnets created by electric currents in coils. Electric motors use electromagnets and permanent magnets to convert electrical energy to mechanical motion.
This document defines magnetic terms and properties, describes different types of magnets, and explains how artificial magnets are produced. It discusses the permeability of various materials, magnetic fields and flux, and uses of the left-hand rule. Induction is demonstrated by magnetizing an iron bar near a permanent magnet. Practical applications of induction in electronics are also outlined, including uses in transmission, transformers, motors, and memory.
The document discusses how electromagnetic induction works to generate electricity using magnets and coils of wire. It explains that changing magnetic fields can induce currents in conductors and that this principle is used in electrical generators. It also describes how transformers work to change voltage levels, using step-up transformers to increase voltage for long-distance transmission and step-down transformers to decrease voltage for safe household use.
This document describes principles of electromagnetic induction and various experiments conducted by Michael Faraday. It explains Faraday's law of induction and Lenz's law. It then discusses the working principles of AC generators and transformers. AC generators produce alternating current using a coil rotating in a magnetic field with slip rings. Transformers use the principle of electromagnetic induction to change voltage levels using a primary and secondary coil around an iron core, with different turn ratios determining voltage increase or decrease.
As electric field, that is, force per unit charge is a vector quantity; it can be used to represent overall effect of electric field in system of electric charges. Similarly electric field can be used in pictorial form to describe the overall intensity of the field. Copy the link given below and paste it in new browser window to get more information on Electric Field Lines www.askiitians.com/iit-jee-electrostatics/electric-field-lines/
This document provides an introduction to electromagnetism. It discusses how electricity and magnetism are different facets of the same electromagnetic force. It covers the history of electromagnetism from ancient observations of amber and lodestone to Maxwell's equations unifying electricity and magnetism. The document also describes magnetic fields and forces, electromagnetic induction, electromagnets, Tesla coils, the electromagnetic spectrum, and potential health effects of low-frequency electromagnetic fields.
The document is a presentation about magnetic fields and field lines. It defines magnetic field as the space around a magnet where magnetic force can be felt. It describes how to locate magnetic fields using iron filings or a compass, and defines magnetic field lines as the paths that an independent north pole would take in a magnetic field. It discusses the properties of strong and weak magnetic fields based on the closeness of field lines, and types of magnetic fields such as uniform and non-uniform. Key properties of magnetic field lines are that they are continuous closed curves, give the direction of the magnetic field, and do not intersect.
Magnetism is produced by magnets which have north and south poles and magnetic field lines. The earliest magnets were naturally occurring lodestone. Magnets attract opposite poles and repel like poles. The Earth itself acts like a giant bar magnet due to its nickel-iron core. Magnetic substances are composed of small magnetic domains that align when exposed to an external magnetic field. Electricity and magnetism are related because electric currents produce magnetic fields. Electromagnets are coils of wire that produce strong magnetic fields when electric current passes through. Galvanometers use electromagnets to measure electric current. Electric motors convert electric current into rotational motion using electromagnetic induction. Generators also use electromagnetic induction to produce electric current from mechanical motion. Direct
The document discusses electricity and magnetism. It explains that electric charges create electric fields and moving charges experience magnetic forces. Charges and electric currents produce both electric and magnetic fields, known as electromagnetic fields. Permanent magnets have their own magnetic fields, and magnetism is the properties and interactions of magnets. Electromagnets are magnets created by electric currents in coils. Electric motors use electromagnets and permanent magnets to convert electrical energy to mechanical motion.
This document defines magnetic terms and properties, describes different types of magnets, and explains how artificial magnets are produced. It discusses the permeability of various materials, magnetic fields and flux, and uses of the left-hand rule. Induction is demonstrated by magnetizing an iron bar near a permanent magnet. Practical applications of induction in electronics are also outlined, including uses in transmission, transformers, motors, and memory.
This document discusses magnetic fields and their properties. It explains that magnets have two poles, north and south, and that like poles repel while unlike poles attract. It defines magnetic fields as representing magnetic forces that act at a distance without physical contact. It describes magnetic field lines and their properties, including that their direction shows the field orientation and strength increases with closer spacing. It discusses the force on moving charges in magnetic fields, including how this causes circular or spiral motion, and explains the Hall effect where a magnetic field perpendicular to current flow in a conductor creates a voltage across it.
An electromagnet is a magnet that runs on electricity. Unlike a permanent magnet, the strength of an electromagnet can easily be changed by changing the amount of electric current that flows through it. ... An electromagnet works because an electric current produces a magnetic field. Electromagnetism is produced when an electrical current flows through a simple conductor such as a length of wire or cable, and as current passes along the whole of the conductor then a magnetic field is created along the whole of the conductor.
Electromagnetic induction builds on the concept of magnets and magnetic fields in grade 10. Most of the work covered here is quite clear and straight forward.
This document provides an overview of magnetism and magnetic fields. It discusses how magnets have been known for centuries and were used for navigation. It explains that all magnetic phenomena result from forces between electric charges in motion. It describes the properties of magnets including poles, magnetic fields, and how cutting a magnet produces two magnets. The document also discusses how the Earth itself acts as a magnet and how compasses use the Earth's magnetic field.
This document provides an overview of basics of electrical engineering, specifically focusing on magnets and magnetism. It defines different types of magnets including permanent magnets, temporary magnets, and electromagnets. It describes magnetic domains, magnetic dipoles, magnetic fields, flux, and various laws of magnetism including Biot-Savart law, Ampere's law, force law, and Faraday's law. It also discusses applications such as solenoids, transformers, and generators.
Magnets have north and south poles and magnetic fields created by electron arrangement. Molecular theory explains magnetism at the atomic level, with molecular magnets aligning in materials. Electric currents create magnetic fields, demonstrated by patterns with iron filings. Electromagnets are coils that can be magnetized and demagnetized by switching current on and off. Moving coil meters like the milliammeter measure current through magnetic interactions between the coil and a permanent magnet.
The document discusses various topics related to magnetism including:
- The ancient discovery of magnetism in lodestone by the Chinese in 2000 BC who used it for navigation.
- The properties of magnets including having magnetic fields with poles that attract or repel other magnets and magnetic materials.
- Induced magnetism caused by an external magnetic influence.
- Differences between magnetic, non-magnetic, and magnetized materials and how to test for magnetism.
- Electrical and physical methods of magnetization and demagnetization.
- Plotting magnetic field lines using a compass to map field patterns.
1. Michael Faraday discovered electromagnetic induction in 1831 through experiments showing that a changing magnetic field can induce an electric current in a nearby conductor.
2. Faraday's law of induction states that the induced electromotive force (emf) in a conductor is equal to the rate of change of magnetic flux through the conductor.
3. This discovery established the basis for technologies such as electric generators, transformers, electric motors, and inductors which are crucial components of modern electric power systems and electronics.
Electromagnetism is a branch of physics involving the study of the electromagnetic force, a type of physical interaction that occurs between electrically charged particles. The electromagnetic force usually exhibits electromagnetic fields such as electric fields, magnetic fields, and light, and is one of the four fundamental interactions (commonly called forces) in nature. The other three fundamental interactions are the strong interaction, the weak interaction, and gravitation.[1] At high energy the weak force and electromagnetic force are unified as a single electroweak force.
This document discusses electric fields and forces. It explains that electric charge comes from electrons and protons in atoms, and that rubbing materials together can transfer electrons, creating a separation of positive and negative charges. It also describes how conductors, insulators, and semiconductors differ in how easily they allow charge to flow through or remain separated.
Electricity, magnetism and electromagnetismairwave12
Atoms contain protons, electrons, and neutrons. Protons are positively charged, electrons are negatively charged, and they are located on the outer edges of atoms. The movement and concentration of electrons creates static electricity and electric currents. Static electricity builds up a charge without flowing, while electric current flows from high voltage to low voltage, such as through wires in a circuit. Current can be direct (DC) or alternating (AC). Magnets have north and south poles and magnetic fields that interact with electric fields through electromagnetic induction, which is the basis for technologies like electric motors, generators, and transformers.
Quantum theory provides a framework to understand phenomena at the atomic scale that cannot be explained by classical physics. It proposes that energy is emitted and absorbed in discrete units called quanta. This explains observations like the photoelectric effect where electrons are only ejected above a threshold frequency. Light behaves as both a wave and particle - a photon. Similarly, matter exhibits wave-particle duality as demonstrated by electron diffraction. At the quantum level, only probabilities, not definite values, can be predicted. Quantum mechanics is applied to describe atomic structure and spectra.
Lenz's law states that the direction of an induced current is such that it creates its own magnetic field opposing the change in magnetic flux that created it. This ensures the conservation of energy. When a conductor moves through a magnetic field, it experiences a force opposite to its direction of motion due to the induced current. Similarly, if the magnetic field changes, it induces a current that creates a secondary field opposing the change in the original field. This phenomenon of electromagnetic induction and the opposing induced current explained by Lenz's law has various applications like eddy current braking, transformers, and quantum levitation.
This document discusses various topics related to electromagnetism including magnetic field lines, the direction of magnetic fields, electromagnets, Tesla coils, the electromagnetic spectrum, effects of ELF-EMF radiation on human cells, examples of electromagnetic radiation, and uses of electromagnetic waves. It provides introductions to key concepts and principles of electromagnetism.
1. When a current-carrying wire passes through a magnetic field perpendicular to it, the wire experiences a force perpendicular to both the wire and the magnetic field. Reversing either the current or the magnetic field reverses the direction of the force.
2. A coil carrying a current in a magnetic field experiences a turning force due to the interaction between the magnetic fields. In a DC motor, this principle is used to convert electrical energy to mechanical motion as the turning coil is connected to a power source via a split-ring commutator.
3. The split-ring commutator continuously reverses the current in the coil to keep it turning in one direction. The coil is wound around a soft iron
EEE Introduction to Capacitors and Charging and Discharging of capacitors.Sukhvinder Singh
Capacitors are energy storage devices composed of conductive plates separated by an insulator. The capacitance of a capacitor depends on the plate area, distance between plates, and the dielectric material. An ideal capacitor acts as an open circuit for DC but not AC. Charging a capacitor causes its voltage to rise nonlinearly, while discharging causes voltage to fall nonlinearly. Capacitors in parallel combine via addition of the reciprocals of individual capacitances, while capacitors in series combine via addition of the reciprocals of individual capacitances.
B.Tech sem I Engineering Physics U-III Chapter 1-THE SPECIAL THEORY OF RELATI...Abhi Hirpara
The document discusses Einstein's theory of special relativity. It provides background on Einstein's two postulates: 1) the laws of physics are the same in all inertial frames of reference, and 2) the speed of light in a vacuum is the same for all observers regardless of their motion. It describes how these postulates led Einstein to develop the Lorentz transformations, which show that time and space are relative between different frames of reference moving at a constant velocity with respect to each other.
1) Charles Augustine de Coulomb published his law in 1785 stating that the force between two point charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.
2) He used a torsion balance to measure the attractive and repulsive forces between charged objects and determine that the magnitude of the force depends on the medium between the charges.
3) Coulomb's law can be used to calculate the force between two charges, as well as the electric field and applications include calculating force or distance between charges and the force on a point from multiple charges using the superposition principle.
The document discusses the concept of electromagnetic induction. It begins by defining key terms like magnetic flux and explaining Faraday's experiments which demonstrated that a changing magnetic field can induce an electromotive force (emf) in a circuit. It then states Faraday's Law of electromagnetic induction, which says that a changing magnetic flux induces an emf. It also explains Lenz's Law, which describes the direction of the induced current. The document provides expressions for calculating the induced emf and current. It discusses different methods of inducing emf, like changing the magnetic field or area of a coil. It also covers related topics like eddy currents, self-induction, and mutual induction.
1. Laminating the core breaks up the conductive material into thinner sheets separated by insulating material. This increases the resistance to eddy currents by forcing them to travel longer, more tortuous paths through the laminations.
2. Cutting teeth into the core reduces the cross-sectional area available for eddy currents to flow. With a smaller area, less current can flow and induce smaller magnetic fields, resulting in lower losses.
3. Both techniques reduce eddy current losses by making it more difficult for currents to flow through the conductive material in closed loops in response to changing magnetic fields. This is done by either increasing the resistance and path
This document discusses magnetic fields and their properties. It explains that magnets have two poles, north and south, and that like poles repel while unlike poles attract. It defines magnetic fields as representing magnetic forces that act at a distance without physical contact. It describes magnetic field lines and their properties, including that their direction shows the field orientation and strength increases with closer spacing. It discusses the force on moving charges in magnetic fields, including how this causes circular or spiral motion, and explains the Hall effect where a magnetic field perpendicular to current flow in a conductor creates a voltage across it.
An electromagnet is a magnet that runs on electricity. Unlike a permanent magnet, the strength of an electromagnet can easily be changed by changing the amount of electric current that flows through it. ... An electromagnet works because an electric current produces a magnetic field. Electromagnetism is produced when an electrical current flows through a simple conductor such as a length of wire or cable, and as current passes along the whole of the conductor then a magnetic field is created along the whole of the conductor.
Electromagnetic induction builds on the concept of magnets and magnetic fields in grade 10. Most of the work covered here is quite clear and straight forward.
This document provides an overview of magnetism and magnetic fields. It discusses how magnets have been known for centuries and were used for navigation. It explains that all magnetic phenomena result from forces between electric charges in motion. It describes the properties of magnets including poles, magnetic fields, and how cutting a magnet produces two magnets. The document also discusses how the Earth itself acts as a magnet and how compasses use the Earth's magnetic field.
This document provides an overview of basics of electrical engineering, specifically focusing on magnets and magnetism. It defines different types of magnets including permanent magnets, temporary magnets, and electromagnets. It describes magnetic domains, magnetic dipoles, magnetic fields, flux, and various laws of magnetism including Biot-Savart law, Ampere's law, force law, and Faraday's law. It also discusses applications such as solenoids, transformers, and generators.
Magnets have north and south poles and magnetic fields created by electron arrangement. Molecular theory explains magnetism at the atomic level, with molecular magnets aligning in materials. Electric currents create magnetic fields, demonstrated by patterns with iron filings. Electromagnets are coils that can be magnetized and demagnetized by switching current on and off. Moving coil meters like the milliammeter measure current through magnetic interactions between the coil and a permanent magnet.
The document discusses various topics related to magnetism including:
- The ancient discovery of magnetism in lodestone by the Chinese in 2000 BC who used it for navigation.
- The properties of magnets including having magnetic fields with poles that attract or repel other magnets and magnetic materials.
- Induced magnetism caused by an external magnetic influence.
- Differences between magnetic, non-magnetic, and magnetized materials and how to test for magnetism.
- Electrical and physical methods of magnetization and demagnetization.
- Plotting magnetic field lines using a compass to map field patterns.
1. Michael Faraday discovered electromagnetic induction in 1831 through experiments showing that a changing magnetic field can induce an electric current in a nearby conductor.
2. Faraday's law of induction states that the induced electromotive force (emf) in a conductor is equal to the rate of change of magnetic flux through the conductor.
3. This discovery established the basis for technologies such as electric generators, transformers, electric motors, and inductors which are crucial components of modern electric power systems and electronics.
Electromagnetism is a branch of physics involving the study of the electromagnetic force, a type of physical interaction that occurs between electrically charged particles. The electromagnetic force usually exhibits electromagnetic fields such as electric fields, magnetic fields, and light, and is one of the four fundamental interactions (commonly called forces) in nature. The other three fundamental interactions are the strong interaction, the weak interaction, and gravitation.[1] At high energy the weak force and electromagnetic force are unified as a single electroweak force.
This document discusses electric fields and forces. It explains that electric charge comes from electrons and protons in atoms, and that rubbing materials together can transfer electrons, creating a separation of positive and negative charges. It also describes how conductors, insulators, and semiconductors differ in how easily they allow charge to flow through or remain separated.
Electricity, magnetism and electromagnetismairwave12
Atoms contain protons, electrons, and neutrons. Protons are positively charged, electrons are negatively charged, and they are located on the outer edges of atoms. The movement and concentration of electrons creates static electricity and electric currents. Static electricity builds up a charge without flowing, while electric current flows from high voltage to low voltage, such as through wires in a circuit. Current can be direct (DC) or alternating (AC). Magnets have north and south poles and magnetic fields that interact with electric fields through electromagnetic induction, which is the basis for technologies like electric motors, generators, and transformers.
Quantum theory provides a framework to understand phenomena at the atomic scale that cannot be explained by classical physics. It proposes that energy is emitted and absorbed in discrete units called quanta. This explains observations like the photoelectric effect where electrons are only ejected above a threshold frequency. Light behaves as both a wave and particle - a photon. Similarly, matter exhibits wave-particle duality as demonstrated by electron diffraction. At the quantum level, only probabilities, not definite values, can be predicted. Quantum mechanics is applied to describe atomic structure and spectra.
Lenz's law states that the direction of an induced current is such that it creates its own magnetic field opposing the change in magnetic flux that created it. This ensures the conservation of energy. When a conductor moves through a magnetic field, it experiences a force opposite to its direction of motion due to the induced current. Similarly, if the magnetic field changes, it induces a current that creates a secondary field opposing the change in the original field. This phenomenon of electromagnetic induction and the opposing induced current explained by Lenz's law has various applications like eddy current braking, transformers, and quantum levitation.
This document discusses various topics related to electromagnetism including magnetic field lines, the direction of magnetic fields, electromagnets, Tesla coils, the electromagnetic spectrum, effects of ELF-EMF radiation on human cells, examples of electromagnetic radiation, and uses of electromagnetic waves. It provides introductions to key concepts and principles of electromagnetism.
1. When a current-carrying wire passes through a magnetic field perpendicular to it, the wire experiences a force perpendicular to both the wire and the magnetic field. Reversing either the current or the magnetic field reverses the direction of the force.
2. A coil carrying a current in a magnetic field experiences a turning force due to the interaction between the magnetic fields. In a DC motor, this principle is used to convert electrical energy to mechanical motion as the turning coil is connected to a power source via a split-ring commutator.
3. The split-ring commutator continuously reverses the current in the coil to keep it turning in one direction. The coil is wound around a soft iron
EEE Introduction to Capacitors and Charging and Discharging of capacitors.Sukhvinder Singh
Capacitors are energy storage devices composed of conductive plates separated by an insulator. The capacitance of a capacitor depends on the plate area, distance between plates, and the dielectric material. An ideal capacitor acts as an open circuit for DC but not AC. Charging a capacitor causes its voltage to rise nonlinearly, while discharging causes voltage to fall nonlinearly. Capacitors in parallel combine via addition of the reciprocals of individual capacitances, while capacitors in series combine via addition of the reciprocals of individual capacitances.
B.Tech sem I Engineering Physics U-III Chapter 1-THE SPECIAL THEORY OF RELATI...Abhi Hirpara
The document discusses Einstein's theory of special relativity. It provides background on Einstein's two postulates: 1) the laws of physics are the same in all inertial frames of reference, and 2) the speed of light in a vacuum is the same for all observers regardless of their motion. It describes how these postulates led Einstein to develop the Lorentz transformations, which show that time and space are relative between different frames of reference moving at a constant velocity with respect to each other.
1) Charles Augustine de Coulomb published his law in 1785 stating that the force between two point charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.
2) He used a torsion balance to measure the attractive and repulsive forces between charged objects and determine that the magnitude of the force depends on the medium between the charges.
3) Coulomb's law can be used to calculate the force between two charges, as well as the electric field and applications include calculating force or distance between charges and the force on a point from multiple charges using the superposition principle.
The document discusses the concept of electromagnetic induction. It begins by defining key terms like magnetic flux and explaining Faraday's experiments which demonstrated that a changing magnetic field can induce an electromotive force (emf) in a circuit. It then states Faraday's Law of electromagnetic induction, which says that a changing magnetic flux induces an emf. It also explains Lenz's Law, which describes the direction of the induced current. The document provides expressions for calculating the induced emf and current. It discusses different methods of inducing emf, like changing the magnetic field or area of a coil. It also covers related topics like eddy currents, self-induction, and mutual induction.
1. Laminating the core breaks up the conductive material into thinner sheets separated by insulating material. This increases the resistance to eddy currents by forcing them to travel longer, more tortuous paths through the laminations.
2. Cutting teeth into the core reduces the cross-sectional area available for eddy currents to flow. With a smaller area, less current can flow and induce smaller magnetic fields, resulting in lower losses.
3. Both techniques reduce eddy current losses by making it more difficult for currents to flow through the conductive material in closed loops in response to changing magnetic fields. This is done by either increasing the resistance and path
1) This document discusses electromagnetic induction, including Faraday's experiments and laws. It describes how changing magnetic flux induces an emf in a circuit.
2) Faraday's first law states that a changing magnetic flux induces an emf in a circuit. His second law says the induced emf is proportional to the rate of change of magnetic flux.
3) Lenz's law describes how the induced current will flow in a direction to oppose the change producing it, in accordance with the law of conservation of energy.
The document discusses magnetic circuits and materials. It covers the course objectives which are to understand the construction and working principles of electrical machines and transformers, and to apply principles of DC machines and transformers to analyze characteristics, losses, performance and efficiency. The overview discusses magnetic circuits, laws governing them, flux linkage, inductance, energy, induced EMF, losses, and types of magnetic field systems. It also discusses DC machines, transformers, their construction, principles of operation, characteristics, testing, and losses. Faraday's laws of electromagnetic induction and concepts like mutual induction, Lenz's law, and Fleming's rules are explained. Key terms discussed include reluctance, permeance, induced EMF, self and mutually induced EMF.
1. Michael Faraday discovered electromagnetic induction in 1831 when he found that a changing magnetic field can generate an electric current.
2. According to Faraday's laws of electromagnetic induction, a changing magnetic flux induces an electromotive force (emf) in a circuit. The magnitude of the induced emf is directly proportional to the rate of change of magnetic flux through the circuit.
3. Lenz's law states that the direction of the induced current is such that it creates its own magnetic field to oppose the original change in magnetic flux that created it.
- Michael Faraday demonstrated electromagnetic induction by showing that a changing magnetic flux induces an electromotive force (emf) in a circuit. This discovery revolutionized power generation.
- Lenz's law states that the direction of induced current is such that it creates a magnetic field opposing the change in magnetic flux that created it, in accordance with the law of conservation of energy.
- Faraday's laws of electromagnetic induction relate the induced emf to the rate of change of magnetic flux through a circuit. The magnitude of induced emf is directly proportional to the rate of change of magnetic flux.
This document provides an overview of key concepts in magnetic fields and electromagnetic induction:
1. It defines magnetic fields and describes their properties such as strength and direction. Magnetic fields are generated by magnetic objects and electric currents.
2. The interactions between magnetic fields and moving electric charges or currents are explained through concepts like the Lorentz force law and right hand rules.
3. Electromagnetic induction and its governing laws discovered by Faraday and Lenz are summarized, explaining how changing magnetic fields induce electromotive forces (EMFs) in conductors.
4. Self and mutual induction are introduced, where changing currents in conductors induce opposing EMFs due to their own or neighboring conductors' magnetic fields.
This document discusses electromagnetism and several related concepts from physics. It defines electromagnetism as the study of the relationship between electric currents and magnetism. It explains that a current-carrying conductor produces a magnetic field and describes the right hand rule for determining the direction of magnetic fields. It also discusses magnetic fields produced by current-carrying loops and solenoids, as well as the concepts of magnetic flux and electromagnetic induction.
1. An electromagnet works by aligning the atoms in a magnetic material like iron through an electric current, creating a strong magnetic field. The stronger the current, the stronger the magnetic field, up to the point of saturation where all atoms are aligned.
2. Magnets have properties like attracting ferromagnetic materials, opposite poles attracting and like poles repelling, and aligning north to south when free to move. Magnetic field lines form closed loops and never intersect.
3. In a magnetic circuit, magnetic flux is produced by current in a wire and measured in Webers. Magnetomotive force (MMF) drives flux and is measured in Ampere-turns. Permeability indicates a material
This document discusses electromagnetic principles and magnetic circuits. It begins by defining magnets and magnetic fields, including magnetic lines of force and flux. It then discusses electromagnetic relationships such as magnetic flux, reluctance, permeability and hysteresis. It describes different types of magnetic circuits including simple, composite and parallel circuits. It also covers electromagnetic induction, including Faraday's and Lenz's laws. Induced emf can be dynamically or statically induced. Core losses from hysteresis and eddy currents are also summarized.
Faraday's Law of Electromagnetic Induction describes how a changing magnetic field can induce an electric current in a conductor. It has many important applications, including electrical generators, transformers, induction motors, and more. The principles of electromagnetic induction are applied in devices that power our homes and enable modern technologies like mobile devices. However, when doing experiments or working with high voltages, safety precautions must be followed to avoid harm.
this is my investigatory file I made for class XII on the topic electromagnetic induction (EMI).there 2 document with same name 1 is in pdf and another one is in docx.
This document provides an overview of magnetism and magnetic fields. It begins with an introductory activity on magnetism facts. The document then outlines topics to be covered, including magnetic fields, forces on moving charges and currents, and properties of electromagnets and ferromagnets. Examples are provided to demonstrate how to calculate magnetic field strength and forces. The key points are that magnets produce magnetic fields with north and south poles; magnetic fields exert forces on moving charges; and currents generate magnetic fields according to Ampere's law.
e can define motion as the change of position of an object with respect to time. A book falling off a table, water flowing from the tap, rattling windows, etc., all exhibit motion. Even the air that we breathe exhibits motion! Everything in the universe moves
This document discusses magnetism and electromagnetism. It begins by defining magnets and their properties such as polarity and attraction/repulsion. It then discusses how magnetic fields are created by magnets and electric currents. The strength of magnetic fields depends on factors like the current, number of coil turns, and the core material. A changing magnetic field can induce an electric current based on electromagnetic induction. Electromagnets and their applications in devices like speakers and computer monitors are also covered.
1. Electromagnetic induction is the process of using a changing magnetic field to induce a voltage in a conductor. This occurs when the magnetic flux through a loop of wire changes due to the relative motion of a magnet or changes in the strength of the magnetic field.
2. Michael Faraday discovered electromagnetic induction in 1831 through experiments showing that a changing magnetic field can generate an electric current in a nearby wire. This principle is applied in devices like generators, transformers, and inductive chargers.
3. Some key requirements for induction to occur are that the conductor be perpendicular to magnetic field lines and that the magnetic flux through the loop of wire must be changing for a voltage to be induced.
This document discusses magnetic levitation and summarizes:
1. Magnetic levitation works by using magnetic fields to repel magnetic materials and lift or propel objects without touching.
2. It relies on principles of ferromagnetism, diamagnetism, and eddy currents induced in conductors by changing magnetic fields.
3. Magnetic levitation shows potential for fast, smooth mass transit but faces challenges with stability, power requirements, and cooling superconductors.
1. Michael Faraday discovered electromagnetic induction in 1831, showing that a changing magnetic field can generate an electric current.
2. An electric motor works by placing a coil of wire between the poles of a magnet. When current passes through the coil, it experiences a force due to the magnetic field and begins to rotate, converting electrical energy to mechanical energy.
3. Key parts of a motor include an insulated copper wire coil, magnet poles to provide a magnetic field, split rings acting as a commutator to reverse current direction, an axle for the coil to rotate around, and brushes connecting the commutator to a current source.
Electromagnetic induction is the process of using magnetic fields to produce voltage and current in a conductor. Michael Faraday discovered that a changing magnetic flux induces a voltage in any nearby conductor. This effect is known as electromagnetic induction. Lenz's law describes how the direction of induced current is always such that it creates a magnetic field opposing the original change in magnetic flux that caused it. Motional emf is a type of electromagnetic induction that occurs when a conductor moves through a magnetic field, such as in electric generators, transformers, electric motors, and railguns.
We have compiled the most important slides from each speaker's presentation. This year’s compilation, available for free, captures the key insights and contributions shared during the DfMAy 2024 conference.
6th International Conference on Machine Learning & Applications (CMLA 2024)ClaraZara1
6th International Conference on Machine Learning & Applications (CMLA 2024) will provide an excellent international forum for sharing knowledge and results in theory, methodology and applications of on Machine Learning & Applications.
ACEP Magazine edition 4th launched on 05.06.2024Rahul
This document provides information about the third edition of the magazine "Sthapatya" published by the Association of Civil Engineers (Practicing) Aurangabad. It includes messages from current and past presidents of ACEP, memories and photos from past ACEP events, information on life time achievement awards given by ACEP, and a technical article on concrete maintenance, repairs and strengthening. The document highlights activities of ACEP and provides a technical educational article for members.
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
Low power architecture of logic gates using adiabatic techniquesnooriasukmaningtyas
The growing significance of portable systems to limit power consumption in ultra-large-scale-integration chips of very high density, has recently led to rapid and inventive progresses in low-power design. The most effective technique is adiabatic logic circuit design in energy-efficient hardware. This paper presents two adiabatic approaches for the design of low power circuits, modified positive feedback adiabatic logic (modified PFAL) and the other is direct current diode based positive feedback adiabatic logic (DC-DB PFAL). Logic gates are the preliminary components in any digital circuit design. By improving the performance of basic gates, one can improvise the whole system performance. In this paper proposed circuit design of the low power architecture of OR/NOR, AND/NAND, and XOR/XNOR gates are presented using the said approaches and their results are analyzed for powerdissipation, delay, power-delay-product and rise time and compared with the other adiabatic techniques along with the conventional complementary metal oxide semiconductor (CMOS) designs reported in the literature. It has been found that the designs with DC-DB PFAL technique outperform with the percentage improvement of 65% for NOR gate and 7% for NAND gate and 34% for XNOR gate over the modified PFAL techniques at 10 MHz respectively.
A SYSTEMATIC RISK ASSESSMENT APPROACH FOR SECURING THE SMART IRRIGATION SYSTEMSIJNSA Journal
The smart irrigation system represents an innovative approach to optimize water usage in agricultural and landscaping practices. The integration of cutting-edge technologies, including sensors, actuators, and data analysis, empowers this system to provide accurate monitoring and control of irrigation processes by leveraging real-time environmental conditions. The main objective of a smart irrigation system is to optimize water efficiency, minimize expenses, and foster the adoption of sustainable water management methods. This paper conducts a systematic risk assessment by exploring the key components/assets and their functionalities in the smart irrigation system. The crucial role of sensors in gathering data on soil moisture, weather patterns, and plant well-being is emphasized in this system. These sensors enable intelligent decision-making in irrigation scheduling and water distribution, leading to enhanced water efficiency and sustainable water management practices. Actuators enable automated control of irrigation devices, ensuring precise and targeted water delivery to plants. Additionally, the paper addresses the potential threat and vulnerabilities associated with smart irrigation systems. It discusses limitations of the system, such as power constraints and computational capabilities, and calculates the potential security risks. The paper suggests possible risk treatment methods for effective secure system operation. In conclusion, the paper emphasizes the significant benefits of implementing smart irrigation systems, including improved water conservation, increased crop yield, and reduced environmental impact. Additionally, based on the security analysis conducted, the paper recommends the implementation of countermeasures and security approaches to address vulnerabilities and ensure the integrity and reliability of the system. By incorporating these measures, smart irrigation technology can revolutionize water management practices in agriculture, promoting sustainability, resource efficiency, and safeguarding against potential security threats.
2. Contents:
Introduction
History
Laws of Magnetic Force
Magnetic Field
Direction of Magnetic Field
Magnetic Effect of Electric Current
Electromagnetic Induction
Faraday’s Laws of Electromagnetic Induction
Induced E.M.F.
Magnetic Hysteresis
3. Introduction
Electromagnetism is the key to the operation of great part
of electrical apparatus found in industry as well as home.
Thus, today magnetism has attained a place of a pride in
electrical engineering.
Without the aid of magnetism, it is impossible to operate
such a device as electrical generators, motors
transformers etc.
Electricity and magnetism are different facets of
Electromagnetism.
Without electromagnetism very few of our modern
devices are possible.
4. History
The origin of electricity is and magnetism sprang
from ancient men’s curiosity over the ability of two
materials, amber and lodestone to attract other
materials.
With the publication of James Clerk Maxwell's 1873
Treatise on Electricity and Magnetism in which the
interactions of positive and negative charges were
shown to be regulated by one force.
An electric current in a wire creates a circular
magnetic field around the wire, its direction
depending on that of the current.
In early 19th century faraday discover
electromagnetic induction.
5. Laws of magnetic force
First law:
Like poles repel each other and unlike poles attract each other.
Second law:
The magnetic forces between two isolated magnetic poles placed in
a medium is directly proportional to the product of the pole strength and
inversely proportional to square of the distance between them.
F α m1 m2 Or F = K m1 m2
d2 d2
Where K is a constant whose value depends upon the surrounding
medium.
K = 1 Where μ0 = Absolute permeability
4𝝅μ0 μr
= Relative permeability
6. Magnetic Field
The magnets exert their influence in the surroundings,
this is called magnet field.
Magnetic field is a quantity that has both direction and
magnitude.
The direction of the magnetic field is taken to be the
direction in which a north pole of the compass needle
moves inside it.
7. Direction of Magnetic Field
(1) Right hand-palm rule :
“First make the thumb and fingers of the right hand
perpendicular to each other and put the thumb along the
wire in the direction of the current and fingers point
towards the point of observation”.
8. (2) Right hand-thumb rule :
“If the thumb is along the direction of current, wrapped fingers will
show the direction of circular magnetic field lines.”
(3) Fleming Left-hand rule :
“Hold out your left hand with forefinger, second finger and thumb at
right angle to one another. If the fore finger represents the direction of
the field and the second finger that of the current, then thumb gives the
direction of the force.”
9. (4) Right hand rule :
“Hold out the right hand with the first finger, second and
thumb at right angle to each other. If finger represent the
direction of the line of force, the thumb points in the
direction of motion or applied force, then second finger
point in the direction of the induced current.”
10. Magnetic Effect of Electric current
When a conductor carries a current, magnetic lines of
force are set around the length of the conductor.
Magnetic field produced by the current flowing in the
conductor.
Magnetic lines of force in the form of concentric circle
around the conductor.
The direction of the line of force depends upon the
direction of the current
11. Electromagnetic Induction
When the magnetic flux linking a conductor changes, an
e.m.f. is produced in the conductor. If the conductor
forms a closed circuit, a current will flow in it. This
phenomenon is known as Electromagnetic induction.
12. Faraday's Laws of Electromagnetic
Induction
Faraday's First Law:
“Any change in the magnetic field of a coil of wire will cause an
emf to be induced in the coil. This emf induced is called induced
emf and if the conductor circuit is closed, the current will also
circulate through the circuit and this current is called induced
current. Method to change magnetic field.”
(1)By moving a magnet towards or away from the coil
(2)By moving the coil into or out of the magnetic field.
(3)By changing the area of a coil placed in the magnetic field
(4)By rotating the coil relative to the magnet.
13. Faraday's Second Law:
“It states that the magnitude of emf induced in the coil is equal to
the rate of change of flux that linkages with the coil. The flux
linkage of the coil is the product of number of turns in the coil and
flux associated with the coil.”
Consider a magnet approaching towards a coil. Here we consider two
instants at time T1 and time T2. Flux linkage with the coil at time, T1 =
NΦ1 Wb Flux linkage with the coil at time, T2 = NΦ2 wb Change in flux
linkage = N(Φ2 - Φ1) Let this change in flux linkage be, Φ = Φ2 - Φ1 So,
the Change in flux linkage = NΦ Now the rate of change of flux linkage =
NΦ / t Take derivative on right hand side we will get The rate of change of
flux linkage = NdΦ/dt But according to Faraday's law of electromagnetic
induction, the rate of change of flux linkage is equal to induced emf.
Considering Lenz's Law.
14. Lenz’s law :
“The direction of current induced in a conductor by a
changing magnetic field due to Faraday's law of
induction will be such that it will create a field that
opposes the change that produced it.”
Lenz's law is shown by the negative sign in Faraday's law of
induction:
15. Induced e.m.f.
When a moving charge cuts through the flux lines of a
magnetic field, it experiences a force given by
F = qv×B. To see what occurs, consider Fig. where
the crosses represent a flux field B directed away from
the reader. When conducting bar ab is moving to the
right with velocity v, then every charge within the bar
is moving to the right, cutting past flux lines, with a
velocity v. The consequence of this is that a force of
F = qv×B is exerted on every charge within the bar
where the direction of the vector F is along the bar,
directed from b to a. This force amounts to an emf
within the bar, tending to produce a current from b to
a. If the bar is part of a circuit, or connected to a
galvanometer as in Fig. 1 above, that emf will cause a
current to flow. If the bar is not part of a circuit, then
what will happen is that the free electrons in the bar
will all move toward end b, making end b negative and
end a positive.
16. Emf induced in a moving conductor. The emf induced in a straight
conductor of length l moving with velocity v perpendicular to a
magnetic field B is
1) E = Blv
where B, l and v are mutually perpendicular. The emf is in volts
when B is in webers/m2, l is in meters, and v is in m/sec.
If the velocity vector v makes an angle θ with the direction of the
magnetic field, 1) becomes
2) E = Blv sin θ
17. Magnetic Hysteresis
Magnetic hysteresis is an important phenomenon and refers to the
irreversibility of the magnetisation and demagnetisation process. When a
material shows a degree of irreversibility it is known as hysteretic. We will
now explore the physics behind ferromagnetic hysteresis.
When a demagnetised ferromagnetic material is placed in an applied
magnetic field the domain that has a direction closest to that of the applied
field grows at the expense of the other domains. Such growth occurs by
motion of the domain walls. Initially domain wall motion is reversible, and
if the applied field is removed the magnetisation will return to the initial
demagnetised state. In this region the magnetisation curve is reversible and
therefore does not show hysteresis.
The crystal will contain imperfections, which the domain boundaries
encounter during their movement. These imperfections have an associated
magnetostatic energy. When a domain wall intersects the crystal
imperfection this magnetostatic energy can be eliminated as closure
domains form. This pins the domain wall to the imperfection, as it is a local
energy minima.
18. The applied magnetic field provides the energy to allow the domain wall to
move past the crystal imperfection, but the domains of closure cling to the
imperfection forming spike-like domains that stretch as the domain wall
moves further away. Eventually these spike domains snap off and the
domain wall can move freely. As the spike domains snap off there is a
discontinuous jump in the boundary leading to a sharp change in the
magnetic flux, which can be detected by winding a coil around the specimen
connected to a speaker. In doing so, crackling noises are heard
corresponding to the spike domains breaking away from the domain walls.
This phenomenon is known as the Barkhausen effect.
Eventually all the domain walls will have been eliminated leaving a single
domain with its magnetic dipole moment pointing along the easy axis
closest to the direction of the applied magnetic field. Further increase in
magnetisation can occur by this domain rotating away from the easy
direction to an orientation parallel to that of the externally applied field. The
magnetisation of the material at this stage is called the saturation
magnetisation (see Figure J) . The ease of this final rotation is dependent on
the magnetocrystalline energy of the material; some materials require a
large field to reach this saturation magnetisation.
19. If the external applied field is removed the
single domain will rotate back to the easy
direction in the crystal. A demagnetising
field will be set up due to the single domain,
and this field initiates the formation of
reverse magnetic domains as these will
lower the magnetostatic energy of the
sample by reducing the demagnetising field.
However the demagnetising field is not
strong enough for the domain walls to be
able to grow past crystal defects so they can
never fully reverse back to their original
positions when there is no external applied
field. This results in the hysteresis curve as
some magnetisation will remain when there
is no external applied field. This
magnetisation is called the remanent
magnetisation, Br. The field required to
reduce the magnetisation of the sample to
zero is called the coercive field Hc. And the
saturation magnetisation Bs is the
magnetisation when all the domains are
aligned parallel to the external field. These
are shown on the schematic below:
20. Reference :
Electrical Technology Volume 1
(B.L. Theraja, A.K. Theraja)
A. Beiser(1987) Concepts of modern physics (4th ed.)
McGraw-Hill (International)
University of Cambridge
(TLP library ferromagnetic materials-hysteresis)