However, for some loads, even this circuit might be an improvement over a simple resistor. Suppose you had a black box instead of an LED. Because of lightbulbs or motors or something inside of it ...

That is, a 1 KΩ and a 2 KΩ resistor in series will draw as much ... you can also measure reactance using a similar circuit. As a simple thought experiment, then, imagine that Rd=1.

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 ...

The classic approach for sensing an ac load's current requires a transformer or sensing resistor. The transformer may be expensive,... This circuit provides different ways to measure the current ...