Which equation is used to compute total voltage (VT) in a series circuit?

The correct equation for computing total voltage (VT) in a series circuit is that the total voltage is the sum of the individual voltage drops across each component in the circuit. In a series connection, the voltage provided by the power source is divided among the components, and each component exhibits a certain voltage drop. Therefore, the total voltage can be represented as the sum of these voltage drops: VT = V1 + V2 + V3.

This principle is rooted in Kirchhoff's Voltage Law, which states that the sum of the electrical potential differences (voltage) around any closed network is zero. Thus, the total voltage supplied by the source must be equal to the sum of the voltages across all components in series, confirming that option A accurately reflects this relationship.