When the current goes to zero in an AC circuit, which way does the compass needle turn?

When considering how the compass needle behaves in an alternating current (AC) circuit, it is important to understand the relationship between electric current and magnetic fields. In an AC circuit, the direction of current flow changes periodically, which in turn affects the magnetic field around the conductor.

When the current is flowing positively, the magnetic field produced around the wire influences the compass needle to point in a certain direction. As the AC current reaches zero, the magnetic field weakens and eventually disappears, resulting in the compass needle being influenced by the Earth's magnetic field rather than the changing magnetic field created by the AC current.

In this specific case, as the current transitions to zero, the compass needle aligns with the Earth's magnetic field, which typically points towards the magnetic north. This means that, ideally, the compass needle would turn to point towards the north when the current ceases, making the choice of North the most accurate response. Thus, when the current goes to zero in an AC circuit, the compass needle will indeed align with the Earth's magnetic field, pointing North.