Alarm system with sensor and buzzer in Arduino - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to set the sensor pin as input.

Arduino

const int sensorPin = 2;
void setup() {
  pinMode([1], INPUT);
}
void loop() {}

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A13

BOUTPUT

CbuzzerPin

DsensorPin

Attempts:

3 left

💡 Hint

Common Mistakes

Using the buzzer pin instead of the sensor pin.

Setting the pin mode to OUTPUT instead of INPUT.

The sensor pin must be set as input to read sensor data.

2fill in blank

medium

Complete the code to read the sensor value inside the loop.

Arduino

const int sensorPin = 2;
int sensorValue;
void setup() {
  pinMode(sensorPin, INPUT);
}
void loop() {
  sensorValue = [1](sensorPin);
}

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AanalogRead

BdigitalWrite

CdigitalRead

DanalogWrite

Attempts:

3 left

💡 Hint

Common Mistakes

Using digitalWrite() instead of digitalRead().

Using analogRead() for a digital sensor.

Use digitalRead() to read a digital sensor value from the sensor pin.

3fill in blank

hard

Fix the error in the code to turn on the buzzer when the sensor is triggered.

Arduino

const int sensorPin = 2;
const int buzzerPin = 8;
void setup() {
  pinMode(sensorPin, INPUT);
  pinMode(buzzerPin, OUTPUT);
}
void loop() {
  if (digitalRead(sensorPin) == [1]) {
    digitalWrite(buzzerPin, HIGH);
  } else {
    digitalWrite(buzzerPin, LOW);
  }
}

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AHIGH

BLOW

CINPUT

DOUTPUT

Attempts:

3 left

💡 Hint

Common Mistakes

Comparing sensor reading to LOW instead of HIGH.

Using pin modes instead of HIGH/LOW values.

The buzzer should turn on when the sensor reads HIGH (triggered).

4fill in blank

hard

Fill both blanks to make the buzzer beep for 1 second when triggered.

Arduino

const int sensorPin = 3;
const int buzzerPin = 9;
void setup() {
  pinMode(sensorPin, INPUT);
  pinMode(buzzerPin, OUTPUT);
}
void loop() {
  if (digitalRead(sensorPin) == [1]) {
    digitalWrite(buzzerPin, HIGH);
    delay([2]);
    digitalWrite(buzzerPin, LOW);
  }
}

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AHIGH

BLOW

C1000

D500

Attempts:

3 left

💡 Hint

Common Mistakes

Using LOW instead of HIGH for sensor trigger.

Using 500 ms delay instead of 1000 ms.

The buzzer should turn on when sensor reads HIGH and delay 1000 milliseconds (1 second).

5fill in blank

hard

Fill all three blanks to create a dictionary-like structure that maps sensor states to buzzer actions.

Arduino

const int sensorPin = 4;
const int buzzerPin = 10;
void setup() {
  pinMode(sensorPin, INPUT);
  pinMode(buzzerPin, OUTPUT);
}
void loop() {
  int state = digitalRead(sensorPin);
  switch(state) {
    case [1]:
      digitalWrite(buzzerPin, [2]);
      break;
    case [3]:
      digitalWrite(buzzerPin, LOW);
      break;
  }
}

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AHIGH

BLOW

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up HIGH and LOW values in cases.

Using pin modes instead of HIGH/LOW values.

When sensor state is HIGH, buzzer turns HIGH; when LOW, buzzer turns LOW.