What does the term "voltage drop" refer to?

The term "voltage drop" refers specifically to the reduction in voltage that occurs in an electrical circuit as electrical current flows through resistive components, such as wires and devices. This drop occurs due to the inherent resistance in these components, which causes some of the electrical energy to be dissipated as heat, thus resulting in a lower voltage being delivered to the load at the end of the circuit.

When a current travels through a conductor, the resistance of the conductor affects how much voltage is available at the load. A well-designed circuit takes voltage drop into account to ensure that loads receive adequate voltage for proper function. For instance, in longer runs of wire, more pronounced voltage drop can be observed, which is why it's essential to consider wire gauge and circuit layout.

The other options do not accurately define voltage drop. The concept of an increase in voltage under an overloaded condition is not related to voltage drop but rather to circuit behavior during overloads. The total voltage supplied to a circuit is a different measure and does not specifically describe the phenomenon of voltage drop. Lastly, the voltage at the load end refers to the specific voltage measurement taken at the device being powered, which can be influenced by the voltage drop but is not synonymous with the term itself.