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help with voltage and electricity c/o physical science

true or false      iron is easily magnetized because it has pairs of electrons which gspin in the same direction
i think this is true
true or false      voltage can be induced in a wire coal by moving the wire coal through a magnetic field
i think this is true
if there were no current in the wire running through the magnet, what could  you do to induce an electric current?


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Richard P. | Fairfax County Tutor for HS Math and ScienceFairfax County Tutor for HS Math and Sci...
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The first statement is essentially true.   The conduction band electrons in single domain of iron do have parallel spins.  Since the electron has a magnetic moment, a magnetic field results.
The second is almost true. A voltage will be induced in a wire coil moving in a non-uniform magnetic  field.  Alternatively, a coil in uniform magnetic field can be rotated on a transverse axis to induce a voltage.
I am not sure how to interpret the third one.   If the wire mentioned is a coil wound around the magnet, A current could be induced by withdrawing the magnet from the coil.
Michael A. | Math/Physics/Science TutorMath/Physics/Science Tutor
What 's up L from Jacksonville.
First answer...TRUE.  This is called Ferromagnetism
next answer...TRUE, but why?  See "Faraday's Law."
last answer...You can induce a current using Faraday's Law.  Consider the second question.  If I move a coil through a magnetic field (or vice versa), this induces a voltage.
Ohm's law says that voltage = current x resistance.  So, induced voltage will create an induced current.