Engineering Q&A
LearnQwestrum Engineering360 · Electrical & Electronics
What is Ohm's law?
Ohm's law states that voltage equals current times resistance (V = I × R) — the fundamental relationship for analyzing electrical circuits and selecting components.
Exam tip: keep SI units consistent end-to-end, write the governing relation symbolically before substituting, and sanity-check magnitude and sign.
Understand the concept
For a linear resistor at constant temperature, doubling voltage doubles current. Ohm's law helps size wires, fuses, and resistors and is the starting point for Kirchhoff's laws and circuit analysis.
Practical note
Real devices may not be perfectly ohmic — diodes, transistors, and motors have nonlinear behavior. Power dissipation P = V × I matters for heating and component ratings.
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