Assuming a current is flowing, what increases the strength of the magnetic field of a coiled electrical wire? select all that apply. straightening the wire changing the direction of the current flow adding more coils to the wire placing a metal bar within the coils stopping the current

There are two ways how the strength of the magnetic field can be increased: 1. by increasing the number of loops of wire around the iron core or 2. by increasing the current or voltage. So, assuming a current is flowing adding more coils to the wire will increase the strength of the magnetic field of coiled electrical wire.