What is the standard voltage for domestic electrical outlets?

The standard voltage for domestic electrical outlets in many countries, including the United States and Canada, is 120 volts. This voltage is designed to safely power typical home appliances, lighting, and electronic devices. The adoption of 120 volts is based on safety considerations and efficiency for household circuits, allowing for a balance between minimizing the risk of electric shock and providing sufficient power for everyday use.

In contrast, other voltage levels, such as 240 volts, are usually reserved for heavier appliances like dryers and ovens that require more power to operate. Voltages like 60 volts and 30 volts are not standard for domestic outlets and are typically used in specialized equipment or applications. Thus, 120 volts is the universally accepted standard for standard household outlets, making this option the correct choice.