Of course, the resistor also has to have a sufficient view of the LED. You might use this as a safety light that only works in the dark. A simple circuit, but it just goes to show that we tend to ...

Instead of simply replacing the outdated bulb, we decided to build a small dark detecting circuit with 2 yellow LEDs based on this Evil Mad Scientist Laboratories design. After successfully ...

Using properties of a series circuit, the sum of the voltages across the LED and resistor R must equal the supply voltage. \({V_s} = {V_{LED}} + {V_R}\) Now substitute the supply voltage (\(6V ...