If a wire carrying current produces magnetic field around it, why its not attracted to nearby metals ? In a general household.
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It sort of is. The field will distort near conductive materials (cause a weak alignment of magnetic polarity in the metallic object) but it won’t have enough force to cause movement at the scale you want it to. The field is just too weak and the mass is too high.
If you coil the wire around the metal, so the magnetic field repeats itself and thus adds strength to the field in the dominant direction, then you can create a strong enough field to do something. This is the idea behind electromagnets.
The field loses strength with distance from the region of current (basic inverse square law; even really strong fields dissipate rapidly with distance). When coiling a wire, you keep the “new” field within the still-strong range of the next-along field, so there is more then one field involved, and the field strength adds together and extends further in the direction of coiling.
We are bathed in electromagnetic fields all the time, everywhere, and they do somewhat distort in our immediate vicinity too. The strengths of the fields is normally tiny because the power of the electromagnetism (or field generator) is relatively tiny and we are “far” from the source, so nothing really is noticeable. Need a strong internal field and almost no friction for even a needle to align to the earth’s magnetic field. A car out on the street though, isn’t going to be aligned with the earth’s field. The presence of the car, though, does modify the shape of the field in its immediate zone of influence. The changes are just so tiny, is all.
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