If our example resistor ended in gold (orange, white, black, gold), its 39 Ohms value could be five percent higher or lower. For a possible minimum of 37.05 or a maximum of 40.95.

The measured value is shown on the OLED display at the front, and in resistor color-code on an enormous symbolic resistor lit by WS2812 RGB LEDs behind.

Resistor noise is white and Gaussian. Purists like to rant that Gaussian noise does not have a defined peak-to-peak value—it’s infinite, they say. True enough because the tails of a Gaussian ...

Using clear visuals and real-life examples, we’ll show you the internal construction of a resistor, explore Ohm’s Law, and demonstrate how resistance is measured in ohms.

The Excel cell formula below calculates the nearest standard 1%-resistor value without using a lookup table or macro. Type or electronically paste the text below into any cell (other than A1).

Question A LED takes a current of 12.5 m A when the voltage across it is 2 V. Draw a suitable circuit and calculate the value of the series resistor needed to operate the LED from a 9 V battery.