With increase in load the load current passing through the circuit increases and hence the voltage drop across the resistance of the components in series path wrt load increase increases causing a drop in the voltage across the load terminals.

Why does voltage drop with load?

Wires carrying current always have inherent resistance, or impedance, to current flow. Voltage drop is defined as the amount of voltage loss that occurs through all or part of a circuit due to impedance. ... This condition causes the load to work harder with less voltage pushing the current.

How does load affect voltage?

Load affects the performance of circuits with respect to output voltages or currents, such as in sensors, voltage sources, and amplifiers. ... If the load impedance is not very much higher than the power supply impedance, the voltages will drop.