Magnetism Laws of Magnetism Magnetic Materials Forces Between Magnets Induced Magnetism Methods of Magnetism & Demagnetization Theory of magnetism Magnetic

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  • MagnetismLaws of MagnetismMagnetic MaterialsForces Between MagnetsInduced MagnetismMethods of Magnetism&DemagnetizationTheory of magnetismMagnetic fieldsMagnetic Properties of MatterMagnetic Effects of a CurrentPlease choose a topicDone By: Siddharth AroraThe font used in this presentation is 1979 If your computer does not have this font it will display in Arial Sorry for the inconvenience caused

  • Like poles _________Unlike poles _______ 1) repel; attract 2) attract; repel 3) explode; melt 4) disintegrate; fly to the moonQuestion 3Question 2Question 1Instructions:Click on the correct answerLaws of magnetism

  • Which ones of the poles are North? 1) A,B 2) none 3) B,C 4) B,DQuestion 3Question 2Question 1Instructions:Click on the correct answerLaws of magnetism

  • Instructions:Click on the correct answerLaws of magnetismMagnetic North is geographical _______ 1) South 2) East 3) Space time continuum 4) Centre of the UniverseQuestion 3Question 2Question 1

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  • Laws of MagnetismWhen a bar magnet is suspended freely it always comes to rest in a north south direction.

  • Magnetic PolesMagnetic South is geographical North.

    Magnetic North is geographical South

  • Magnetic PolesMagnetic poles are located at the side of the magnets.

  • Magnetic & Non-Magnetic MaterialsMagnetic Materials include:IronCobaltNickelThe rest are alloys of these metals such as steel.

  • Forces Between MagnetsLike Poles Attract

    Unlike Poles Repel

  • Induced MagnetismA magnet attracts a non magnetic material by magnetic induction

  • Methods Of MagnetizationHeating and HammeringPlace a steel bar in the north-south direction and heatHammer it while coolingA magnet formed by this method is __________StrongWeakTry This Question

  • Methods Of MagnetizationHeating and HammeringPlace a steel bar in the north-south direction and heatHammer it while coolingA magnet formed by this method is weak

  • Methods Of MagnetizationHeating and HammeringPlace a steel bar in the north-south direction and heatHammer it while coolingA magnet formed by this method is weak

  • Methods of MagnetizationMagnetization by strokingDone as shown in diagramA magnet formed by this method is __________A) StrongB) WeakTry This Question

  • Methods of MagnetizationMagnetization by strokingDone as shown in diagramA magnet formed by this method is weak

  • Methods of MagnetizationMagnetization by strokingDone as shown in diagramA magnet formed by this method is weak

  • Methods of MagnetizationMagnetization using an electric currentA solenoid (a length of copper wire wound into a long coil) is connected to a battery in series.A iron bar is then placed inside the solenoidThe polarities depend no the direction of the flow of the current

    A magnet created in this way is ________ StrongWeak

    Try This Question

  • Methods of MagnetizationMagnetization using an electric currentA solenoid (a length of copper wire wound into a long coil) is connected to a battery in series.A iron bar is then placed inside the solenoidThe polarities depend no the direction of the flow of the current

    A magnet created in this way is strong

  • Methods of MagnetizationMagnetization using an electric currentA solenoid (a length of copper wire wound into a long coil) is connected to a battery in series.A iron bar is then placed inside the solenoidThe polarities depend no the direction of the flow of the current

    A magnet created in this way is strong

  • DemagnetizationA solenoid (a length of copper wire wound into a long coil) is connected to a battery providing alternating current.The magnet is then placed inside the solenoidIt is then removed in an East-West direction

  • Theory of MagnetismMagnetic domains (groups of small atomic magnets) are found in each magnet.A magnet is formed when all the domains point in one direction.

  • Magnetic FieldsThe region around the magnet where its effects can be observed is a magnetic field

  • Magnetic FieldsProperties of magnetic fieldsOutside the magnet the lines start from the north pole and end at the south poleInside the magnet they continue from the south pole to the north pole

  • Magnetic FieldsThe lines never cross each otherThe lines behave as though they are pulled tautThe lines repel each otherLines are close together in a stronger field than a weaker field

  • Magnetic FieldsThe lines tend to pass through a magnetic substance

  • Magnetic Properties of MatterSoft Magnetic MaterialsEasy to magnetizeEasy to demagnetizeCan be used as electromagnetsE.g.: Iron

  • Magnetic Properties of MatterHard Magnetic MaterialsHard to magnetizeHard to demagnetizeCan be used as permanent magnetsE.g.: Steel

  • Magnetic Properties of MatterPermanent magnetsMagnetism is retained for a long time

  • Magnetic Properties of MatterElectromagnetsMagnetic events can only be observed for specific intervals of time

  • Magnetic Properties of MatterThe strength of an electromagnet can be increased by:Passing a larger current through the solenoidIncreasing the number of turns of the solenoid

  • Magnetic Properties of MatterInserting a core of a soft magnetic materialA core of a hard magnetic material cannot be used because____________A) It takes too long to magnetize and demagnetizeB) Its not coolTry This Question

  • Magnetic Properties of MatterInserting a core of a soft magnetic materialA core of a hard magnetic material cannot be used because It takes too long to magnetize and demagnetize

  • Magnetic Properties of MatterInserting a core of a soft magnetic materialA core of a hard magnetic material cannot be used because It takes too long to magnetize and demagnetize

  • Magnetic Effect of a CurrentMagnetic effects of current means that a current flowing in a wire produces a magnetic field round it.As current increases more lines are formed

  • Magnetic Effect of a CurrentMaxwells Corkscrew rule states that the direction of the magnetic field is the same as the direction in which you would turn an ordinary corkscrew to move it in the direction of the current.

  • Magnetic Effect of a CurrentThis can be interpreted as when current is flowing downwards or away from you, the magnetic field is in the clockwise direction

  • Magnetic Effect of a CurrentThe magnetic field when the wire is in the shape of a flat coil or a solenoid, is shown in the diagram