The magnetic field due to current in wires in your home can affect a compass. Discuss the effect in terms of currents, including if they are ac or dc.
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The current in the wire makes a magnetic field, which is circular around the wire. If a compass is placed in this field, the needle will align itself in a direction tangent to the circular magnetic field lines.
When the current is a direct current (dc), the magnitude and direction of the current doesn’t change and therefore magnetic field (B) doesn’t change. When placed at one point, the compass needle will point in one direction at all times.
If the current is an alternating current (ac), the direction of current / reverses after every half-cycle and B also reverses. The compass needle that points in the reverse direction of B (magnetic field) reverses its direction at a point.