float v2;
int pin=A5;
int readVal;
void setup() {
  // put your setup code here, to run once:
  pinMode(pin, INPUT);
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  readVal=analogRead(pin);
  v2=(5.0f/1023)*readVal;
  Serial.println(v2);
  delay(500);
}