Group-1-PHYSICS Magnetic Induction .pptx

Physics

1. Magnetic Induction, Inductance, AC, and LC Circuits GROUP 1 PEDERE, SABLAN, VASQUEZ, SALVADOR, MENDOZA, OBUSA, VILLANUEVA, SABLADA

2. MAGNETIC INDUCTION -Magnetic induction, also known as electromagnetic induction , is the process by which a changing magnetic field in a region of space induces an electric current or voltage in a nearby conductor. -This phenomenon was discovered by Michael Faraday in the 19 th century . -According to Faraday’s law of electromagnetic induction, the induced electromotive force (EMF) in a circuit is directly proportional to the rate of change of magnetic flux through the circuit. -This principle is the basis for many important technologies such as generators, transformers, and inductors.

3. -Electricity from magnetism, known as electromagnetic induction, is the process of generating an electric current or voltage by changing magnetic fields. -This principle is vital for various technologies like generators and transformers, where it’s used to convert mechanical energy into electrical energy or transfer electricity between circuits. ELECTRICITY FROM MAGNETISM

4. Michael Faraday, a brilliant scientist who discovered electromagnetic induction in 1831 .

5. -Faraday’s law of induction states that a change in magnetic flux through a loop of wire induces an electromotive force (EMF) or voltage in the wire . -This induced EMF creates an electric current in the wire if the circuit is closed. In simpler terms , it means that moving a magnet near a coil of wire or changing the magnetic field within the coil will generate an electric current in the wire. -This principle is fundamental to the operation of electric generators, transformers, and many other electrical devices FARADAY’S LAW OF INDUCTION

6. Unveiling Magnetic Flux: The Flow of Magnetism Magnetic flux (4) is a concept in electromagnetism that describes the total amount of m agnetic field passing through a specific area. It's a way to quantify the strength and influence of a magnetic field within a particular region. Imagine a magnetic field like an invisible current of magnetism flowing through space . Each magnetic field line represents the path of this magnetic influence. Magnetic flux is analogous to the flow rate of water in a pipe. Here's a breakdown of the key points : Total Magnetic Field : Magnetic flux considers the strength of the magnetic field and the number of field lines passing through an area. A stronger magnetic field with more concentrated lines will have a higher magnetic flux compared to a weaker field with fewer lines passing through the same area.

7. Area Perpendicular to Field Lines: The orientation of the area matters. Magnetic flux is maximized when the area is perpendicular to the magnetic field lines. Imagine holding a flat plate in front of a bar magnet. If the plate is held flat (perpendicular), many field lines pass through it, resulting in high flux. If you tilt the plate, fewer lines pass through, reducing the flux. Here's an analogy to solidify the concept: Think of water flowing through a pipe: Magnetic Field Strength : Imagine the water pressure as the magnetic field strength. Higher pressure signifies a stronger field. Number of Field Lines : The number of water molecules flowing per second represents the number of field lines passing through the area. More molecules equate to more lines. Area : The pipe's cross-sectional area represents the area we're considering. A wider pipe allows more water to flow (higher flux) compared to a narrow one for the same pressure.

8. By understanding magnetic flux, we can analyze how strongly a magnetic field affects a particular region. This concept plays a crucial role in various electromagnetic phenomena, including Faraday's Law of Induction, which we'll explore next.

9. The Flow of Magnetism: Unveiling Magnetic Field Lines While magnetism doesn't physically flow like a liquid, we can use the concept of "flow" to visualize how magnetic fields behave and interact with their surroundings. Here's a breakdown to understand the flow of magnetism : Magnetic Field Lines: A Visual Representation Imagine a magnet, like a bar magnet. It has a north and south pole. We can't directly see the magnetic field it creates, but we can visualize it using magnetic field lines . These lines are imaginary lines that depict the direction and strength of the magnetic field at any point . They originate from the north pole and terminate at the south pole, never intersecting . The density of the lines indicates the strength of the magnetic field. More concentrated lines represent a stronger field, while sparse lines depict a weaker field.

10. Visualizing the Flow Imagine these magnetic field lines as invisible streams of magnetism flowing through space. The lines show the direction a tiny magnetized compass needle would point if placed anywhere on the line. Think of iron filings sprinkled around a magnet. The way the filings align themselves along invisible lines depicts the flow of the magnetic field . Properties of the Flow Continuous Lines: Magnetic field lines are continuous. They don't abruptly stop or have breaks. They either form closed loops (like around a bar magnet) or extend infinitely outward. No Monopoles: Unlike electric fields, which have positive and negative charges(sources and sinks ), magnetic fields don't have isolated poles. They exist as closed loops or continuous lines .

11. Flow and Interaction The flow of magnetism helps us understand how magnets interact Opposite poles attract (lines converge), while like poles repel (lines diverge ). The flow also explains how moving magnets or changing currents can induce electric fields (Faraday's Law). As the flow of magnetism changes , it creates an electric field in a conductor . Limitations of the Analogy It's important to remember that magnetic fields aren't actual fluids. They are a manifestation of a force field . The flow analogy helps with visualization, but it doesn't capture the full complexity of magnetic interactions.

12. Understanding the Flow: Key Takeaways By understanding the flow of magnetism through magnetic field lines, we can:Visualize the direction and strength of magnetic fields.Predict how magnets will interact with each other . Explain the basis for electromagnetic induction (Faraday's Law ). This concept is fundamental in electromagnetism and helps us understand various phenomena,From the operation of electric motors to the behavior of charged particles in a magnetic field . Unveiling Magnetic Flux: The Essence of Magnetism Through an Area Magnetic flux ($), denoted by the uppercase Phi symbol, is a crucial concept in electromagnetism . It quantifies the total amount of magnetic field that passes through a specific area. Imagine a river flowing through a bridge; magnetic flux is like the amount of water flowing through the bridge opening at any given time. Here's a deeper dive into magnetic flux:

13. Understanding the Essence Magnetic Field & Area : Magnetic flux considers both the strength of the magnetic field and the size and orientation of the area it interacts with,Stronger Field, Higher Flux: A stronger magnetic field, with more concentrated field lines passing through a specific area, translates to a higher magnetic flux . Area Matters : The orientation of the area also plays a role. Magnetic flux is maximized when the area is perpendicular to the magnetic field lines. Imagine holding a flat plate in front of a bar magnet. If the plate is held flat, many field lines pass through it, resulting in high flux. Tilting the plate reduces the number of lines passing through, lowering the flux. Units and Measurement The SI unit of magnetic flux is the weber ( Wb ). One weber represents one volt-second ( Vs ). To calculate magnetic flux, we can use the following equation:BA cos (0)where: (Phi) is the magnetic flux in webers ( Wb ) B is the magnetic field strength in teslas (T) A is the area of the surface in square meters (m³) 8 (theta) is the angle between the magnetic field and the normal ( perpendicular) to the area

14. Key Points to Remember Higher Magnetic Field Strength : A stronger magnetic field, with more concentrated lines,will result in a higher magnetic flux even for the same area. Larger Area: A larger area perpendicular to the field lines will allow more lines to pass through , increasing the magnetic flux. Angle Matters: The angle between the field and the area is crucial. If the area is not perpendicular (090"), the effective area through which the field lines pass is reduced, lowering the flux ( cos (8) term in the equation). Magnetic Flux and Everyday ApplicationsMagnetic flux plays a vital role in various areas: Generators : Generators use rotating magnets to create a changing magnetic field that induces a current in coils of wire. The amount of current generated is directly related to the magnetic flux through the coils.

15. Transformers: Transformers use a changing magnetic flux to transfer electrical energy from one circuit to another. By manipulating the number of turns in the coils, they can change the voltage based on the principle of magnetic flux. Electric Motors: Electric motors utilize electromagnets to create a rotating magnetic field.This changing magnetic field interacts with permanent magnets in the motor, causing it to spin. The strength of the interaction depends on the magnetic flux produced by the electromagnets . Understanding magnetic flux is fundamental to grasping the interaction between magnetic fields and conductors. It forms the foundation for numerous electromagnetic technologies that power our world.  

16. The Key to Induction: A Change in Magnetic Flux Faraday's Law of Induction revolutionized our understanding of electromagnetism, This law reveals a fascinating connection: a changing magnetic field can induce an electric cument in a conductor. But what's the secret ingredient? The key les in a change in magnetic flux   Unveiling Magnetic Flux Imagine a magnetic field like an invisible current of magnetism fowing through space. Each magnetic field line represents the path of this magnetic influence. Magnetic flux () quantifies the total amount of magnetic field passing through a specific area. Think of it like the flow rate of water in a pipe. Stronger Magnetic Field: A stronger magnetic field with more concentrated lines translates to a higher magnetic flux Larger Area: A larger area perpendicular to the field lines allows more lines to pass through. increasing the flux

17. The Spark of Change Faraday's Law hinges on the concept of a changing magnetic flux through a conductor. The change can occur in several ways: Moving Magnet : Imagine a magnet being moved towards or away from a coll of wire. As the magnet moves, the magnetic field lines passing through the coll's loops change. This change in magnetic flux induces an electric current in the cof Visualizing the Change Imagine a coil of wire held near a magnet. As you move the magnet closer to the coll , more magnetic field ines pass through the col's loops, signifying an increase in magnetic flux. This change induces a current in the coil. Conversely moving the magnet away from the coil reduces the flux, again inducing a current but in the opposite direction according to Lenz's Law (covered in the next slide)

18. The Takeaway: Why Does Change Matter ? A constant magnetic field, even a strong one, won't induce a current in a conductor using Faraday's Law , it's the change in the magnetic field that disrupts the existing magnetic environment around the conductor. This disruption creates an electromotive force ( emf ). essentially a voltage push that drives the flow of current in the conductor. The greater the change in magnetic flux, the larger the induced emf and the stronger the current. Examples of Change in Magnetic Flux : Generators: Generators use rotating magnets to create a continuously changing magnetic field through coils of wire. This changing flux induces a current in the ecoils , generating electricity Changing Current: If a current flows through a coil of wire, it creates a magnetic field. By changing the cument in the coil (Increasing or decreasing), the magnetic field also changes. This change in magnetic field, in turn, can induce a current in another nearby coil

19. Understanding the importance of a changing magnetic flux is crucial for grasping Faraday's Law and its numerous applications in our daily lives.   The Opposing Force: Unveiling Lenz’s Law Faraday's Law of Induction tells us that a changing magnetic field can induce an electric current in a conductor . But there's another crucial aspect to consider: Lenz's Law. This law explains the direction of the induced current Transformers: Transformers work by changing the magnetic flux through coils due to changes in current. This allows them to transfer electrical energy at different voltage levels. Metal Detectors: Metal detectors use a changing magnetic field to detect the presence of metal objects that alter the magnetic field in their vicinity

20. Heinrich Friedrich Emil Lenz Heinrich Lenz, a German physicist, formulated this law in 1834 , states that the induced current in a conductor always flows in a direction that creates a magnetic field opposing the change in the original magnetic field . In simpler terms, the induced current acts like a shield, trying to prevent the change in the magnetic field that produced it.

21. Visualizing the Opposition   Imagine a magnet being moved towards a coil of wine. As the magnet approaches, the magnetic field lines passing through the coll increase. According to Lenz's Law, the induced current in the coil will flow in a direction that generates its own magnetic field. This induced m agnetic field will oppose the increase in the original magnetic field caused by the approaching magnet Herner's an analogy : Imagine pushing a heavy door open. The door represents the original magnetic field. As you push (causing a change), the door naturally resists your push (opposing the change) Similarly, the induced current acts like an opposing force to the change in the original magnetic field. Consequences of Lenz's Law Lenz's Law has several important consequences: It helps us predict the direction of the induced current.

22. It explains why a changing magnetic field can transfer energy. The induced current does work to oppose the change, which requires energy This energy comes from the source that's causing the change in the magnetic field ( eg , the movement of the magnet ). It forms the basis for the operation of many electromagnetic devices like generators and motors.   Examples of Lenz's Law in Action   Generators: In a generator, a rotating magnet induces a current in a coil. The induced current , according to Lenz's Law, creates a magnetic field that opposes the rotation of the magnet. This opposition requires energy, which comes from the mechanical force used to rotate the magnet. Transformers : Transformers use changing magnetic fields to transfer electrical energy Lenz's Law ensures that the induced current in the secondary coll creates a magnetic field that opposes the change in the primary coil, allowing for efficient energy transfer.

23. Lenz's Law, coupled with Faraday's Law, provides a complete picture of electromagnetic induction. It helps us understand how changing magnetic fields create currents, predict in their direction , and explains the energy transfer involved.

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