Principle of transformer class 12

Electromagnetic Induction What Is Electromagnetic Induction? Electromagnetic Induction was discovered by Michael Faraday in 1831, and James Clerk Maxwell mathematically described it as Faraday’s law of induction. Electromagnetic Induction is a current produced because of voltage production (electromotive force) due to a changing magnetic field. This either happens when a conductor is placed in a moving magnetic field (when using an AC power source) or when a conductor is constantly moving in a stationary magnetic field. As per the setup given below, Michael Faraday arranged a conducting wire attached to a device to measure the voltage across the circuit. When a bar magnet is moved through the coiling, the voltage detector measures the voltage in the circuit. Through his experiment, he discovered that there are certain factors that influence this voltage production. They are: • Number of Coils: The induced voltage is directly proportional to the number of turns/coils of the wire. Greater the number of turns, greater is voltage produced • Changing Magnetic Field: Changing magnetic field affects the induced voltage. This can be done by either moving the magnetic field around the conductor or moving the conductor in the magnetic field. You may also want to check out these concept related to induction: • • • Watch the video and solve the NCERT exercise in the chapter Magnetic Effects of Electric Current Class 10 Applications of Electromagnetic Induction Based on his experiment...

We know that the electric power coming into our homes is produced very far away from our homes. They are transmitted with the help of cables. But during transmission, energy is lost. The voltage is raised at the power plants before transmission to reduce the loss of energy. The voltage is reduced and distributed to our houses at the power stations. To perform all these functions, we need an electrical component called Transformer. This article will learn about types of transformers, their working principle, and some applications. What is a Transformer? A transformer is an electrical device that transfers electrical energy from one circuit to another circuit through electromagnetic induction and mutual induction. It is most commonly used to increase (‘step up’) or decrease (‘step down’) voltage levels between circuits without a change in the frequency of AC between circuits. Types of Transformers Depending on the operating voltage, there are mainly two types of transformer. These are as follows: 1. Step-down Transformer:A step-down transformer converts the primary voltage level to a lower voltage across the secondary output. For step-down transformers, the number of windings is higher across the primary side than the secondary side. Therefore, the overall winding ratio of secondary and primary will always remain less than \(1\). 2. Step-up Transformer: Step-up transformer increases the low primary voltage to a high secondary voltage. In this type of transformer, the number ...

Generators and Transformers In this article, let us discuss two important mechanical equipment that are widely used, generators and transformers. A generator converts one form of energy into another. Let us know in detail the working principle of transformer, types and applications of generators and transformers. Table of Contents: • • • • • • • • • • • • • • • • What is the Working Principle of Generator? It consists of a rectangular coil with a number of copper wires wound over an iron core. The coil is called the armature. It is used to increase the magnetic flux. A strong permanent magnet is placed, and the armature is rotated between the magnets where the magnetic lines are perpendicular to the axis of the armature. There are two slip rings connected to the arms of the armature. They are used to provide movable contact. Two metallic brushes are connected to the slip rings to pass current from the armature to the slip rings. The current is passed through a load resistance, which is connected across the slip rings. At different time intervals, the position of the armature keeps changing. When the magnetic field lines are perpendicular to the coil, the coil is rotated in the magnetic field, and the induced e.m.f produced increases. This happens in this position because of the number of intercepting magnetic field lines maximum. What are the Advantages of AC Generators? Advantages of AC generators are: • The time spent on maintenance is very less as there are no brushes. ...

changing the frequency. Transformer can increaseor decrease the voltage or current in a circuit. WORKING PRINCIPLE: Transformer works on the principle of Mutualinduction between two windings (Primary and secondary) linked by commonmagnetic flux. When source of alternating voltage is connected to the Primarycoil the magnetic flux produced in primary induces flux in secondary coil too. Thefrequency remain same. Construction:- i t consist of twoinductive winding and a steel core which is laminated. The core is constructedby stacking sheets of steel with minimum air gap between the two. The steel isused because of its high permeability and low hysteresis loss. The stackingmust of alternating sides of joint. Ajit had a high tension tower erected on his farmland. He kept complaining to the authorities to remove it as it was occupying a large portion of his land. His uncle, who was a teacher, explained to him the need for erecting these towers for efficient transmission of power. As Ajit realized its significance, he stopped complaining. Answer the following questions: (a) Why is it necessary to transport power at high voltage? (b) A low power factor implies large power loss. Explain. (c) Write two values each displayed by Ajit and his uncle. Additional Problems(77) The student engineer of a campus radio station wishes to verify the effectiveness of the lightning rod on the antenna mast (Figure). The unknown resistance R x ​ is between points C and E. Point E is a true ground, bu...

Hint: A transformer is a device which is used to transfer electrical energy from one circuit to another. Its working is based on the mutual induction of two coils placed in vicinity of each other. Complete step by step solution: A transformer is an electrical device which is used to couple one circuit to another. The transformer transforms the electrical energy from one circuit to another. A transformer is constructed using two coils wound around a laminated steel core. All the components are electrically insulated from one another. The basic working principle of a transformer is mutual inductance between the coils of the transformer. In a transformer, we have a primary coil and a secondary coil. An input signal is fed to the primary coil. The change in flux in secondary coil due to flow of current in primary coil induces an e.m.f in secondary coil. The amount of e.m.f produced in the coils depends on the number of windings of the coils. On the basis of windings, we have two types of transformers: 1) Step-down transformer: The primary coil has more windings than secondary coil. It decreases or steps down the voltage. Electricity is transmitted over long distances at high voltage in order to reduce resistance offered by cables. In order to increase the voltage, a step-up transformer is used before transmitting and a step-down transformer is used to lower the voltage at the receiving station. Note: We use a laminated steel core in a transformer because it reduces losses due ...

Hint: A transformer is a device which is used to transfer electrical energy from one circuit to another. Its working is based on the mutual induction of two coils placed in vicinity of each other. Detailed step by step answer: A transformer is an electrical device which is used to couple one circuit to another. The transformer transforms the electrical energy from one circuit to another. A transformer is constructed using two coils wound around a laminated steel core. All the components are electrically insulated from one another The basic working principle of a transformer is mutual inductance between the coils of the transformer. In a transformer, we have a primary coil and a secondary coil. An input signal is fed to the primary coil. The change in flux in secondary coil due to flow of current in primary coil induces an e.m.f in secondary coil. The amount of e.m.f produced in the coils depends on the number of windings of the coils. On the basis of windings, we have two types of transformers: Step-down transformer: The primary coil has more windings than the secondary coil. It decreases or steps down the voltage.

Transformers are important electronic devices; they are used to supply an amount of electricity from one electric circuit to another; in this transaction, there are no changes in the frequency of the flowing electric charge. Windings, insulated materials, conservators, etc, are parts of a transformer. These parts play an essential role in the functions of the DC transformer. In addition, transformers are extensively used in various electronic devices; the following paragraphs will explain what a dc transformer is, its applications, and its working principles. Transformers A transformer is defined as an electric device that transforms the electric current from one electric circuit to a different electric circuit without making any changes in the frequency of the current. A transformer is also considered a static electric device because, unlike generators, transformers do not have a moving part. The transformers work on the principle of mutual induction under a magnetic field. Over the years, transformers have evolved as a major industrial tool; these devices make it easy and safe to supply electricity from one circuit to another. As a result, the introduction of transformers has revolutionised many countries’ industrial growth and power supply. Different types of transformers A transformer can be classified based on various parameters, such as its usage, construction, and purpose; a transformer may be as small as a mobile phone adapter and even can be used in supplying ele...

Electromagnetic Induction What Is Electromagnetic Induction? Electromagnetic Induction was discovered by Michael Faraday in 1831, and James Clerk Maxwell mathematically described it as Faraday’s law of induction. Electromagnetic Induction is a current produced because of voltage production (electromotive force) due to a changing magnetic field. This either happens when a conductor is placed in a moving magnetic field (when using an AC power source) or when a conductor is constantly moving in a stationary magnetic field. As per the setup given below, Michael Faraday arranged a conducting wire attached to a device to measure the voltage across the circuit. When a bar magnet is moved through the coiling, the voltage detector measures the voltage in the circuit. Through his experiment, he discovered that there are certain factors that influence this voltage production. They are: • Number of Coils: The induced voltage is directly proportional to the number of turns/coils of the wire. Greater the number of turns, greater is voltage produced • Changing Magnetic Field: Changing magnetic field affects the induced voltage. This can be done by either moving the magnetic field around the conductor or moving the conductor in the magnetic field. You may also want to check out these concept related to induction: • • • Watch the video and solve the NCERT exercise in the chapter Magnetic Effects of Electric Current Class 10 Applications of Electromagnetic Induction Based on his experiment...

changing the frequency. Transformer can increaseor decrease the voltage or current in a circuit. WORKING PRINCIPLE: Transformer works on the principle of Mutualinduction between two windings (Primary and secondary) linked by commonmagnetic flux. When source of alternating voltage is connected to the Primarycoil the magnetic flux produced in primary induces flux in secondary coil too. Thefrequency remain same. Construction:- i t consist of twoinductive winding and a steel core which is laminated. The core is constructedby stacking sheets of steel with minimum air gap between the two. The steel isused because of its high permeability and low hysteresis loss. The stackingmust of alternating sides of joint. A town situated 2 0 k m away from a power house at 4 4 0 V, requires 6 0 0 K W of electric power at 2 2 0 V. The resistance of transmission line carrying power is 0 . 4 Ω per km. The town gets power from the line through a 3 0 0 0 V − 2 2 0 V step down transformer at a substation in the town. Which of the following is /are correct Ajit had a high tension tower erected on his farmland. He kept complaining to the authorities to remove it as it was occupying a large portion of his land. His uncle, who was a teacher, explained to him the need for erecting these towers for efficient transmission of power. As Ajit realized its significance, he stopped complaining. Answer the following questions: (a) Why is it necessary to transport power at high voltage? (b) A low power factor im...

Hint: A transformer is a device which is used to transfer electrical energy from one circuit to another. Its working is based on the mutual induction of two coils placed in vicinity of each other. Complete step by step solution: A transformer is an electrical device which is used to couple one circuit to another. The transformer transforms the electrical energy from one circuit to another. A transformer is constructed using two coils wound around a laminated steel core. All the components are electrically insulated from one another. The basic working principle of a transformer is mutual inductance between the coils of the transformer. In a transformer, we have a primary coil and a secondary coil. An input signal is fed to the primary coil. The change in flux in secondary coil due to flow of current in primary coil induces an e.m.f in secondary coil. The amount of e.m.f produced in the coils depends on the number of windings of the coils. On the basis of windings, we have two types of transformers: 1) Step-down transformer: The primary coil has more windings than secondary coil. It decreases or steps down the voltage. Electricity is transmitted over long distances at high voltage in order to reduce resistance offered by cables. In order to increase the voltage, a step-up transformer is used before transmitting and a step-down transformer is used to lower the voltage at the receiving station. Note: We use a laminated steel core in a transformer because it reduces losses due ...