resistor calculations

Three vintage dials labeled V, I, and R linked by brass levers and gears around the equation V = I × R, beside the title How Electronics Work, How Ohm's Law Works
How Ohm's Law Works: Mastering Fundamental Electronics Part 04
DIY Electronics
Learn how Ohm's law works: the V = IR relationship, how to solve for voltage, current, or resistance with real units, when the law applies, and how to check your answers with power.