Compared to permanent magnets why are electromagnets more useful in
many modern technologies?
...
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
Answers: 2
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