How does the direction of the electric current, moving across a battery powered device, differ from the direction of travel in the AC current sent to homes and businesses

in a battery, electrons flow from the negative terminal to the positive. In AC, it alternates 120 times per second (60 times persecond one way, 60 times the other way each second)

The direction of the electric current in a battery-powered device and in alternating current (AC) sent to homes and businesses differ in their conventions.

In a battery-powered device, the electric current flows from the positive terminal of the battery towards the negative terminal. This convention is known as conventional current flow. It was established before the discovery of electrons and is based on the observation that positive charges move in response to electric fields. Despite being called conventional current flow, it is actually the movement of negatively charged electrons from the negative terminal towards the positive terminal of the battery that constitutes the electric current.

On the other hand, in AC systems that provide power to homes and businesses, the direction of electric current constantly changes. Alternating current periodically reverses its direction, moving back and forth. This change in direction occurs at a specific frequency, typically 50 or 60 times per second (measured in hertz, Hz). The convention used to represent the direction of AC current is based on the direction of the changing electric field. When the electric field is changing in one direction, the current is said to be flowing in one direction, and when the electric field changes in the opposite direction, the current is said to be flowing in the opposite direction.

To determine the direction of the current in a battery-powered device or an AC system, you can use a variety of tools and techniques. One common method is to use a multimeter, which can measure the flow of electric current and indicate its direction. Another approach is to refer to the circuit diagram or consult the documentation provided with the device or electrical system being used. These resources usually indicate the direction of current flow for each component or wire.