In the circuit the LED's rated current is 20 milliamphers. With a voltage drop across the LED of 1.5 volts, calculate the value of the series resistance R1 necessary to be used if the supply voltage is 12 volts DC.(adsbygoogle = window.adsbygoogle || []).push({});

Here is how I answered this, I am not sure if I am right.

R1=Er1/Ir1

R1= 10.5/.020

R1=525 ohm

Can someone help me please?

This problem has me confused

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# Homework Help: LED Circuit Question

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