Each component has a reference designator (R1, C2, Q3, U4).

( V = I \times R ) (Voltage = Current × Resistance)

Arun showed an electromechanical box. “Relays use a small current to move a switch, allowing a low-power signal to control a high-power circuit—like a messenger pulling a lever from afar.” Mira imagined levers and strings linking distant parts.