Current, voltage and a circuit model
22 min · BeginnerUnderstand the concept
A schematic is a model of how electrical nodes connect. Voltage describes potential difference and current describes charge flow; a resistor approximates a linear element over a supported range. Distinguish the model from the behavior of a real component with tolerances and thermal limits.
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Your exercise
Sketch a source-resistor-return loop. Mark reference ground and use Ohm's law to estimate current for a 5 V source and 1 kΩ resistor.
Practice in simulation or at safe low voltage unless supervised by qualified personnel. Follow official equipment safety guidance.
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Knowledge check
Which current flows through 1 kΩ at 5 V?
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