1. Using Photoresistors with an Arduino

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3. Implement photoresistor circuit5V
analog input 2
photoresistor
10kW

4. Enter and run the following sketch
int val = 0; // variable to store value read at analog pin 2
void setup() {
Serial.begin(9600); // set up to print out text to monitor }
void loop() {
val = analogRead(2); // read analog input pin 2
Serial.println(val); // print value to serial monitor
What happens to the values on your serial monitor when you put your hand over the photoresistor?

5. Implement photoresistor and LED circuits
220Ω
digital pin 11 5V
analog input 2
photoresistor
10kW

6. Enter and run the following sketch
int val = 0; // variable to store value read at analog pin 2
void setup() {
Serial.begin(9600); // set up to print out text to monitor
pinMode(11,OUTPUT); // declare pin 11 as an output }
void loop() {
val = analogRead(2); // read analog input pin 2
Serial.println(val); // print value to serial monitor
if(val < 600) // if statement used to control LED {
digitalWrite(11,HIGH); delay(100);
digitalWrite(11,LOW); delay(100);
How does the photoresistor control the LED?