EARTH SCIENCE
MAGNETISM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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decreasing the voltage of the coil
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increasing the number of coils
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changing the direction of current flow
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altering the material used to make the coils
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Detailed explanation-1: -The polarity of an electromagnet can be changed by changing the direction of electric current through it.
Detailed explanation-2: -The poles of an electromagnet can be changed by reversing the flow of electricity.
Detailed explanation-3: -When you reverse the direction of the current flowing in the wire, the north and south poles are also reversed. When you reverse the current again, the north and south poles reverse again. In fact, each time the current is reversed, the north and south poles will exchange places.
Detailed explanation-4: -What happens when you change the direction of current in an electromagnet? Answer: Unlike a permanent magnet, the strength of an electromagnet can easily be changed by changing the amount of electric current that flows through it. The poles of an electromagnet can even be reversed by reversing the flow of electricity.
Detailed explanation-5: -In order to reverse the polarity of a regular magnet, you need the power of a battery and a coil of copper. For an electromagnet, you will just switch the wires around on the inside.