int readPin = A1;
float V2 = 0;
int readVal;
int delayTime = 1000;

void setup() {
  // put your setup code here, to run once:
pinMode(readPin, INPUT);
Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
readVal = analogRead(readPin);
V2 = (5./1023) * readVal;
Serial.println(V2);
delay(delayTime);
}