EARTH SCIENCE
MAGNETISM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the magnetic field created by forcing electrons to move in different directions.
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An instrument to know the amount of electricity on a magnet
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the magnetic field created by forcing electrons to move in the same direction.
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None of the above
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Detailed explanation-1: -Electromagnets are made of coils of wire with electricity passing through them. Moving charges create magnetic fields, so when the coils of wire in an electromagnet have an electric current passing through them, the coils behave like a magnet.
Detailed explanation-2: -The recognised direction of a magnetic field is from its north pole to its south pole. This direction can be deduced by holding the current carrying conductor in your left hand with the thumb extended pointing in the direction of the electron flow from negative to positive.
Detailed explanation-3: -Bar Magnet and Solenoid The magnetic field produced by electric current in a solenoid coil is similar to that of a bar magnet.
Detailed explanation-4: -The direction of the magnetic field lines depends on the direction of the current flowing through the coil of the electromagnet. Reversing the direction of the electric current reverses the direction of the magnetic field lines which reverses the polarity of the magnet.