If we isolate wire with thin wire and assuming that no heat rejected by wire then does electromagnet work. If it work then it violate conservation of energy.
fabler107
Answered question
2022-11-05
Answer & Explanation
Jackson Trevino
Beginner2022-11-06Added 14 answers
To create a magnetic field requires the expenditure of work. In the case of a coil of wire, the work to create the field is done by the time integral of (voltage x current). Once the current has achieved steady state, that current is then required to sustain the field. When the electrical power to the coil is shut off, the field collapses and induces an amount of current flow in the wire. The electrical energy returned to the coil in this way equals that which it took to create the field in the first place, and energy is conserved.
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