Visualizing Resistance With Arduino

In this instructable, you'll visualize how varying resistors change a circuit. Using a 220 Ohm resistor and a 10K ohm resistor, you'll see the variation in light levels in two LEDs as well as see the variation in the voltage across those circuits by using the serial monitor.

Connect a jumper wire from the GND pin on the Arduino to the long negative line on the left side of your breadboard.

Insert an LED into holes E1 and F1 on your breadboard, with the longer leg in hole F1.

Insert one end of a 220 Ohm resistor into the long negative line on the left of the breadboard, and the other into spot B1 on the breadboard.

Insert one end of a jumper wire into spot H1 on the breadboard, and the other into pin 10 on the Arduino. This wire will provide power to your LED.

Insert one end of a jumper wire into spot C1 on the breadboard, and the other into pin A1 on the Arduino. This wire will measure the resistance in your LED circuit.

Insert one end of a jumper wire into spot C1 on the breadboard, and the other into pin A1 on the Arduino. This wire will measure the resistance in your LED circuit.

Insert one end of a 10K Ohm resistor into the long negative line on the left of the breadoard, and the other into spot B5 on the breadboard.

Insert one end of a jumper wire into spot H5 on the breadboard, and the other into pin 9 on the Arduino. This wire will provide power to your LED.

Insert one end of a jumper wire into spot C5 on the breadboard, and the other into pin A2 on the Arduino. This wire will measure the resistance in your LED circuit.

int resistor1 = A5;

int resistor2 = A4;

int LEDPin1 =10;

int LEDPin2 = 9;

float voltage1;

float voltage2;

void setup() {

Serial.begin(9600);

pinMode(resistor1, INPUT);

pinMode(resistor2, INPUT);

pinMode(LEDPin1, OUTPUT);

pinMode(LEDPin2, OUTPUT);

}

void loop() {

int resistor1Value= analogRead(resistor1);

digitalWrite(LEDPin1, HIGH);

voltage1= resistor1Value*(5.0/1023.0);

Serial.print("Voltage 1 = ");

Serial.println(voltage1);

delay(2000);

int resistor2Value= analogRead(resistor2);

digitalWrite(LEDPin2, HIGH);

voltage2= resistor2Value*(5.0/1023.0);

Serial.print("Voltage 2 = ");

Serial.println(voltage2);

delay(2000); }

Resistor Code