|MadSci Network: Physics|
No, but ... No you can not nullify a magnetic field (if any device generates a magnetic field you can not make it just disappear) However, you can either * shield this magnetic field some materials (like steel) may bend a magnetic field, changing its shape thus making it considerably weaker in some places. However, it will not annihilate the field especially in in the very place where it is being created * counter this magnetic field that is you can make another field which has a similar shape but an opposite sign so that in some places, the sum of both fields will be nearly null. The latter is sometimes called active shielding
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