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grade 7 electricity and magnetism

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  • The area around a magnet where magnetic forces act is called the ......................
    magnetic field.
  • When electric current stops flowing in an electromagnet, the magnetic field ________.
    disappears
  • Define electric field.
    An electric field is the space around a charged object where its electric force is exerted on other charges.
  • define galvanometer
    a device that measures small currents
  • ....... is the relation between magnetism and electricity
    electromagnetism
  • define electric current
    continuous flow of charge
  • difference in electric potential energy per charge is called
    voltage
  • Objects become negatively charged when they ________ electrons
    gain
  • In an electric motor, electric energy changes into ________ energy.
    mechanical or kinetic
  • The magnetic field is strongest at the ....................of a magnet.
    poles - ends
  • Like charges attract each other. t or f
    false
  • In electric force, the greater the amount of charge, the ________ the force.
    stronger
  • What is an Aurora?
    are glowing displays in the night sky happens when energetic electrically charged particles travel along the magnetic field lines and collide with gas atoms in
  • Explain one way to make an electromagnet stronger.
    You can increase the number of wire coils or increase the electric current.
  • mention the 4 methods of charging an object
    conduction - friction - induction - polarization
  • what happens to the potential energy when you pull two opposite charges away from each other
    increases
  • is a material that allows electric charges to move easily through it.
    conductor
  • Define electromagnet.
    solenoid with a ferromagnetic core
  • Define insulator.
    An insulator is a material that resists the flow of electric charges.
  • define Static electricity
    Static electricity is the buildup of electric charge on an object.
  • An electric current can produce a magnetic field. t or f
    true