8. LED Blink

How do you plan to solve it?

Assuming the voltage drop of LED is 1.8v 

From the ohms law formula R=V/I I will calculate the resistor needed to limit the current flows through the LED.

Vs = voltage from arduino pin 5v

Vf = voltage drop through LED 1.8

I = Required amp 0.01A (10miliamp) 

R=Vs-Vf/I  ->   5v-1.8v/0.01A ->  3.2v/0.01A -> 320ohm   R=320ohm (Standard Res is 330ohm)

/*Paste your code here*/

void setup() {
  pinMode(4, OUTPUT);
  
}

void loop() {
	digitalWrite(4, HIGH);
  	delay(400);
  	digitalWrite(4, LOW);
  	delay(800);
}

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