Airframe Electrical 1 Practice Test

Diodes conduct only in one direction, so their orientation in a rectifier is what fixes how current can flow. In a rectifier, the diodes are arranged so that during each half-cycle the current is steered toward the load in the same direction, producing a DC output (though it may be pulsating until filtered). If a diode is oriented incorrectly, it would block current when it should conduct or allow current in the wrong direction, ruining the DC output or even causing a short. So, the orientation determines the path of current and ensures the output polarity is DC. While blocking reverse current is a consequence, the essential point is that the diode direction sets the current flow and the resulting DC output.