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Physics, 19.03.2021 05:50 Bra1nPowers

Compared to permanent magnets why are electromagnets more useful in many modern technologies?
A. Strong permanent magnets are too large to use.
B. By controlling the current electromagnets can be turned on and
off.
C. To use an electromagnet, a power supply is not necessary.
D. In permanent magnets, the strength of the magnetic field is more
consistent

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Answers: 2

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Compared to permanent magnets why are electromagnets more useful in many modern technologies?
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