Magnetism 4

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Magnetism 4

• Electricity and Magnetism Related

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Hans Christian Oersted
Discovered that an electric current causes a
magnetic field
How? Connected a series circuit and
turned on the power. A nearby compass moved!
This Proved there was an
electromagnetism link
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Michael Faraday
Discovered that a magnetic field causes an
electrical current.
How? Moved a wire through
the magnetic field of a strong magnet. Found
that an electric current was produced in the wire.
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Electromagnet
Temporary magnet made by wrapping a current
carrying wire around an iron core.
More coils ____________
More power
More current ____________
More power
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Galvanometer
Moving coil electric current detector.
The amount of deflection of a needle attached to
the coil is proportional to the current passing
through the coil.
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Galvanometer
The accuracy of moving coil meters is dependent
upon..
Having a uniform and constant magnetic field