Transformer Physics Investigatory Project PDF Class 12

Introduction

The transformer is a device used for converting a low alternating voltage to a high alternating voltage or a high alternating voltage into a low alternating voltage. It is a static electrical device that transfers energy by inductive coupling between its winding circuits. Transformers range in size from a thumbnail-sized coupling transformer hidden inside a stage microphone to huge units weighing hundreds of tons used in power plant substations or to interconnect portions of the power grid. All operate on the same basic principles, although the range of designs is wide. While new technologies have eliminated the need for transformers in some electronic circuits, transformers are still found in many electronic devices. Transformers are essential for high-voltage electric power transmission, which makes long-distance transmission economically practical. A transformer is most widely used device in both low and high current circuit. In a transformer, the electrical energy transfer from one circuit to another circuit takes place without the use of moving parts. A transformer which increases the voltages is called a step-up transformer. A transformer which decreases the A.C. voltages is called a step-down transformer. Transformer is, therefore, an essential piece of apparatus both for high and low current circuits.

Principle

The electric transformer works on the fundamental principle of electromagnetic induction, a concept first discovered by Michael Faraday in the 19th century. The transformer consists of two coils of wire, known as the primary and secondary windings, which are usually wound around a common magnetic core. When an alternating current (AC) flows through the primary winding, it generates a changing magnetic field around the coil. According to Faraday’s law of electromagnetic induction, this changing magnetic field induces an electromotive force (EMF) or voltage in the secondary winding. The key principle here is that the transformer relies on the mutual induction between the primary and secondary windings through the magnetic flux linkage.

Construction

A transformer consists of a rectangular shaft iron core made of laminated sheets, well insulated from one another. Two coils
& and  & are wound on the same core, but are well insulated with each other. Note that the both the coils are insulated from the core, the source of alternating e.m.f is connected to , the primary coil and a load resistance R is connected to , the secondary coil through an open switch S. thus there can be no current through the sec. coil so long as the switch is open. For an ideal transformer, we assume that the resistance of the primary & secondary winding is negligible. Further, the energy loses due to magnetic the iron core is also negligible. For operation at low frequency, we may have a soft iron. The soft iron core is insulating by joining thin iron strips coated with varnish to insulate them to reduce energy losses by eddy currents. The input circuit is called primary. And the output circuit is called secondary.

Theory

See PDF for Theory Part

Working

A Transformer based on the Principle of mutual induction according to this principle, the amount of magnetic flux linked with a coil changing, an e.m.f is induced in the neighbouring coil that is if a varying current is set-up in a circuit induced e.m.f. is produced in the neighbouring circuit. The varying current in a circuit produce varying magnetic flux which induces e.m.f. in the neighbouring circuit.

The transformer consists of two coils. They are insulated with each other by insulated material and wound on a common core. For operation at low frequency, we may have a soft iron. The soft iron core is insulating by joining thin iron strips coated with varnish to insulate them to reduce energy losses by eddy currents. The input circuit is called primary. And the output circuit is called secondary.

Efficiency

Efficiency of a transformer is defined as the ratio of output power to the input power i.e.

 

Thus, in an ideal transformer, where there is no power losses, η = 1. But in actual practice, there are many power losses; therefore, the efficiency of transformer is less than one.

Material Required

  • Iron Rod
  • Voltmeter
  • Ammeter
  • Copper wire

Diagram

Procedure

  1. Take thick iron rod and cover it with a thick paper and wind a large number of turns of thin Cu wire on thick paper (say 60). This constitutes primary coil of the transformer.
  2. Cover the primary coil with a sheet of paper and wound relatively smaller number of turns (say 20) of thick copper wire on it. This constitutes the secondary coil. It is a step-down transformer.
  3. Connect p1,p2 to A.C main and measure the input voltage and current using A.C voltmeter and ammeter respectively.
  4. Similarly, measure the output voltage and current through s1 and s2
  5. Now connect s1 and s2  to A.C main and again measure voltage and current through primary and secondary coil of step up transformer.
  6. Repeat all steps for other self-made transformers by changing number of turns in primary and secondary coil.

Observation

  1. We will find that ratio of and  across the two coils is equal to the ratio of number of turns in the coil P to that in the coil S. i.e., Vp/Vs = Np/Ns  —————- (1)
  2. The coil P (to which AC voltage is applied) is called the primary and coil S (in which AC is induced) is called the secondary.
  3. Since coil S is placed very close to the coil P, the power in the primary is transferred into the secondary through mutual induction.
  4. It is clear from equation 1, that by appropriate choice of the turn ratio i.e., Np/Ns, we can obtain a higher voltage or lower voltage in S compared to that in P.

Energy Loss

In practice, the output energy of a transformer is always less than the input energy, because energy losses occur due to a number of reasons as explained below.

  • Loss of Magnetic Flux: The coupling between the coils is seldom perfect. So, whole of the magnetic flux produced by the primary coil is not linked up with the secondary coil.

  • Iron Loss: In actual iron cores in spite of lamination, Eddy currents are produced. The magnitude of eddy current may, however be small. And a part of energy is lost as the heat produced in the iron core.

  • Copper Loss: In practice, the coils of the transformer possess resistance. So, a part of the energy is lost due to the heat produced in the resistance of the coil.

  • Hysteresis Loss: The alternating current in the coil tapes the iron core through complete cycle of magnetization. So, Energy is lost due to hysteresis.

  • Magneto restriction: The alternating current in the Transformer may be set its parts in to vibrations and sound may be produced. It is called humming. Thus, a part of energy may be lost due to humming.

Application of Transformer

  1. Electric Power Transmission: Transformers are crucial in power transmission networks to step up voltage for efficient long-distance transmission and step-down voltage for distribution to end-users.

  2. Voltage Regulation: Transformers help maintain a stable voltage level by adjusting the voltage as needed, ensuring consistent and reliable electrical supply.

  3. Power Distribution: They are used in power distribution systems to provide various voltage levels suitable for residential, commercial, and industrial applications.

  4. Power Supply Units: Transformers are employed in power supply units of electronic devices, converting AC power from outlets to the DC power needed by devices like computers and chargers.

  5. Voltage Transformation: Transformers change the voltage levels, allowing electricity to be transmitted at high voltages to reduce energy losses and then be distributed at lower voltages for use.

  6. Industrial Applications: Transformers power various industrial machinery and equipment by adapting electrical voltage to meet specific operational requirements.

Electrical Appliances: Many electronic devices and appliances use transformers to convert electricity to the required voltage for their operation.

Conclusion

  • The output voltage of the transformer across the secondary coil depends upon the ratio (Ns/Np) with respect to the input voltage.

  • The output voltage of the transformer across the secondary coil depends upon the ratio (Ns/N p) with respect to the input voltage.

  • There is a loss of power between input and output coil of a transformer.

Project PDF Download Link:

Scroll to Top

Return & Refund Policy

Thank you for shopping with us! Please read our refund and return policy carefully before making any purchase.

For Project PDF

Once a user has downloaded or explored a project PDF without watermark on our website, we regret to inform you that we do not offer any return or refunds. This policy is in place to protect the integrity of our content and the value of the resources we provide. We encourage users to thoroughly review project details and ensure compatibility before making a purchase.
If you encounter any issues or have concerns about the quality of our content, please feel free to reach out to us. We are committed to addressing any valid concerns and providing assistance to enhance your experience with our website.

For Working Model

Privacy Policy

At Knowledge Cycle, we are committed to protecting your privacy and safeguarding any personal information you provide to us. This Privacy Policy outlines how we collect, use, and handle your information when you visit and interact with our website knowledecycle.in. Please read this policy carefully to understand our practices regarding your personal data.

Information we collect:

  1. Personal Information: We may collect personal information such as your name, email address, and any other details you voluntarily provide when you interact with our website, subscribe to our newsletter, or engage in our services.
  2. Log Data: When you visit our website, our servers automatically collect certain information, including your IP address, browser type, operating system, referring URLs, pages viewed, and the date and time of your visit. This information is collected to analyze trends, administer the site, track users’ movements, and gather broad demographic information for internal use.
  3. Cookies and Similar Technologies: We use cookies, beacons, and similar technologies to enhance your browsing experience and customize content based on your preferences. These technologies also help us collect information about how you use our website and track your interactions with our content.

Use of collected information:

  1. Personalization: We may use the information collected to personalize your experience on our website, providing you with tailored content, recommendations, and offerings that match your interests.
  2. Communication: We may use your contact information to send you newsletters, updates, promotional materials, and other relevant communications. You can opt out of these communications at any time by following the instructions provided in the email or contacting us directly.
  3. Analytics: The data we collect, including log data and information obtained through cookies, helps us analyze user behavior, improve our website’s functionality, and optimize our content based on user preferences.

Data Retention and Deletion:

We retain your personal information only for as long as necessary to fulfill the purposes outlined in this Privacy Policy, unless a longer retention period is required or permitted by law. Once the information is no longer needed, we will securely delete or anonymize it to prevent unauthorized access, use, or disclosure.

Third-Party Services:

We may use third-party services, such as analytics providers or advertising partners, that collect and process information on our behalf. These third parties are bound by confidentiality agreements and are prohibited from using your personal information for any purpose other than assisting us in providing and improving our services.

Data Security:

We implement appropriate security measures to protect your personal information from unauthorized access, alteration, disclosure, or destruction. However, please note that no method of transmission or storage over the internet is 100% secure, and we cannot guarantee the absolute security of your information.

Changes to the Privacy Policy:

We may update this Privacy Policy from time to time to reflect changes in our practices. We encourage you to review this page periodically to stay informed about our privacy practices.

Contact us:

If you have any questions or concerns about this Privacy Policy or our data practices, please contact us at:
Email: contact.knowledgecycle@gmail.com
Telegram: @official_knowledgecycle

Terms and Condition

These terms and conditions govern your use of knowledgecycle.in (the “Website”) and the services provided therein. By accessing or using the Website, you agree to comply with these terms and conditions. If you do not agree with any part of these terms, please refrain from using the Website.

Use of Content

Intellectual Property:

  • The content, trademarks, logos, and intellectual property rights displayed on the Website are the property of knowledgecycle.in or their respective owners. You do not acquire any ownership rights by using the Website.
  • You may not use any of the trademarks, logos, or other proprietary information without the prior written consent of knowledgecycle.in or the respective owners

Use Conduct

  • You agree to use the Website only for lawful purposes and in a manner that does not infringe upon the rights of others, restrict or inhibit anyone else’s use and enjoyment of the Website, or violate any applicable laws.
  • You agree not to engage in any activity that may interfere with or disrupt the Website, such as transmitting viruses, spam, or harmful code.

No Refund Policy

  • Due to the nature of the services provided, knowledgecycle.in operates with a strict no-refund policy. Once you have purchased any investigatory project PDF, Working Model or any other paid services, no refunds will be provided.
  • It is your responsibility to review and confirm your selection before making any purchase


Modifications and Termination

About Us

Welcome to Knowledge Cycle!
At Knowledge Cycle, we are passionate about sharing knowledge and empowering individuals with valuable information. Our platform, knowledecycle.in, is dedicated to providing investigatory project PDFs, insightful blogs, and now, innovative physics working models. Whether you’re a student or an avid learner, we aim to be your go-to resource for educational materials and thought-provoking content.

Our mission:

Our mission is to bridge the gap between curiosity and knowledge. We believe that learning should be accessible to everyone, and we strive to make high-quality educational resources readily available. Through our investigatory project PDFs, engaging blogs, and hands-on physics models, we aim to inspire intellectual growth, critical thinking, and a thirst for knowledge.

What we offers:

  • Investigatory Project PDFs: We understand the importance of hands-on learning and independent research. That’s why we provide a diverse collection of investigatory project PDFs across various topics related to Science. Whether you’re working on a school project, seeking inspiration for your report file, or simply exploring new ideas, our PDFs will equip you with the necessary insights and guidance.
  • Informative Blogs: We write knowledgeable and informative blogs on a wide array of topics. From science and technology to arts and culture, our blogs cover a broad spectrum of subjects to cater to diverse interests. Dive into our articles, expand your knowledge, and stay updated with the latest trends and discoveries.
  • Physics Working Models: We now offer a range of innovative physics working models designed to enhance your understanding of scientific principles through practical application. These models serve as excellent educational tools for students and educators alike, making complex concepts more accessible and engaging.

Why choose knowledge cycle?

  • Quality Content: We prioritize quality in all our offerings. Our investigatory project PDFs, blogs, and working models undergo a meticulous review process to ensure accuracy, relevance, and credibility. You can trust the information you find on our platform to be reliable and up-to-date.
  • User-Friendly Experience: Navigating our website is a breeze. We’ve designed it with user experience in mind, making it easy for you to find the resources you need quickly. Our intuitive search functionality and organized categories enable effortless exploration, ensuring a seamless journey on our platform.
  • Continuous Growth: Learning is a lifelong journey, and we’re committed to supporting your intellectual growth. We regularly update our content library, introducing new investigatory project PDFs, blogs, and working models to keep you inspired and motivated. Be sure to check back often and discover new learning opportunities.

Embark on a knowledge-filled adventure with Knowledge Cycle. Whether you’re seeking investigatory project PDFs, intriguing blogs, or innovative physics models, we’ve got you covered. Join our community of learners, expand your horizons, and unlock the boundless potential of knowledge.