Passive vs active buzzer difference in Arduino - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to turn on an active buzzer connected to pin 8.

Arduino

const int buzzerPin = 8;

void setup() {
  pinMode(buzzerPin, OUTPUT);
  digitalWrite(buzzerPin, [1]);
}

void loop() {
  // Buzzer is on
}

Drag options to blanks, or click blank then click option'

AHIGH

BLOW

CINPUT

DOUTPUT

Attempts:

3 left

💡 Hint

Common Mistakes

Setting the pin to LOW turns the buzzer off.

Confusing pinMode with digitalWrite.

To turn on an active buzzer, you set the pin to HIGH.

2fill in blank

medium

Complete the code to generate a tone on a passive buzzer connected to pin 9.

Arduino

const int buzzerPin = 9;

void setup() {
  pinMode(buzzerPin, OUTPUT);
}

void loop() {
  tone(buzzerPin, [1]);
  delay(1000);
  noTone(buzzerPin);
  delay(1000);
}

Drag options to blanks, or click blank then click option'

ALOW

B1000

CHIGH

D5000

Attempts:

3 left

💡 Hint

Common Mistakes

Using HIGH or LOW instead of a frequency.

Using too high frequency that the buzzer can't play.

The tone() function needs a frequency in Hertz. 1000 Hz is a common tone frequency.

3fill in blank

hard

Fix the error in the code to stop the passive buzzer sound.

Arduino

const int buzzerPin = 7;

void setup() {
  pinMode(buzzerPin, OUTPUT);
  tone(buzzerPin, 2000);
  delay(500);
  [1](buzzerPin);
}

void loop() {}

Drag options to blanks, or click blank then click option'

AnoTone

BdigitalWrite

Ctone

DpinMode

Attempts:

3 left

💡 Hint

Common Mistakes

Using digitalWrite to stop the tone doesn't work.

Calling tone again without parameters won't stop the sound.

To stop a tone on a passive buzzer, use noTone(pin).

4fill in blank

hard

Fill both blanks to create an array of structs that maps buzzer types to their control methods.

Arduino

struct BuzzerControl {
  const char* type;
  const char* method;
};

BuzzerControl controls[2] = {
  { "active", [1] },
  { "passive", [2] }
};

Drag options to blanks, or click blank then click option'

A"digitalWrite(HIGH)"

B"tone(frequency)"

C"digitalWrite(LOW)"

D"noTone()"

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up control methods for active and passive buzzers.

Using noTone for active buzzers.

Active buzzers are controlled by digitalWrite(HIGH), passive buzzers by tone(frequency).

5fill in blank

hard

Fill all three blanks to complete the code that plays a 1kHz tone for 1 second on a passive buzzer, then stops it.

Arduino

const int buzzerPin = 6;

void setup() {
  pinMode(buzzerPin, OUTPUT);
  tone([1], [2]);
  delay(1000);
  [3](buzzerPin);
}

void loop() {}

Drag options to blanks, or click blank then click option'

AbuzzerPin

B1000

CnoTone

Dtone

Attempts:

3 left

💡 Hint

Common Mistakes

Using tone instead of noTone to stop the sound.

Swapping pin and frequency arguments.

The tone() function needs the pin and frequency, then noTone() stops the sound.

Practice

1. What is the main difference between a passive and an active buzzer in Arduino projects?

easy

A. Active buzzers beep with just power; passive buzzers need a signal to produce sound.

B. Passive buzzers beep with just power; active buzzers need a signal to produce sound.

C. Both buzzers require a signal to beep, but active buzzers are louder.

D. Active buzzers cannot produce sound without a microcontroller.

Solution

1. Step 1: Understand buzzer types

   Active buzzers have built-in oscillators and beep when powered. Passive buzzers need an external signal to create sound.

2. Step 2: Compare their operation

   Active buzzers only need power (HIGH voltage) to beep, while passive buzzers require a PWM or tone signal to generate sound.

3. Final Answer:

   Active buzzers beep with just power; passive buzzers need a signal to produce sound. -> Option A

4. Quick Check:

   Active = power only, Passive = signal needed [OK]

Hint: Active buzzers beep on power; passive need tone signals [OK]

Common Mistakes:

• Confusing which buzzer needs a signal
• Thinking both buzzers work the same way
• Assuming active buzzers need tone() function

2. Which Arduino function is typically used to control an active buzzer?

easy

A. tone()

B. pulseIn()

C. analogWrite()

D. digitalWrite()

Solution

1. Step 1: Identify buzzer control methods

   Active buzzers only need power on/off control, so digitalWrite() is used to set HIGH or LOW voltage.

2. Step 2: Match function to buzzer type

   tone() is for passive buzzers to generate frequencies, so it is not used for active buzzers.

3. Final Answer:

   digitalWrite() -> Option D

4. Quick Check:

   Active buzzer uses digitalWrite() [OK]

Hint: Active buzzer uses digitalWrite(), passive uses tone() [OK]

Common Mistakes:

• Using tone() for active buzzer
• Confusing analogWrite() with digitalWrite()
• Trying pulseIn() which reads signals, not outputs

3. What will be the output if you run this Arduino code with a passive buzzer connected to pin 8?

void setup() {
  pinMode(8, OUTPUT);
  tone(8, 1000); // 1000 Hz tone
}
void loop() {}

medium

A. No sound will be produced because tone() is incorrect here.

B. The buzzer will beep continuously at maximum volume.

C. The buzzer will beep at 1000 Hz frequency.

D. The buzzer will beep once and stop.

Solution

1. Step 1: Analyze the code for passive buzzer

   The code uses tone(8, 1000) which sends a 1000 Hz signal to pin 8, suitable for passive buzzers.

2. Step 2: Understand buzzer behavior

   Passive buzzers produce sound only when receiving a frequency signal, so it will beep continuously at 1000 Hz.

3. Final Answer:

   The buzzer will beep at 1000 Hz frequency. -> Option C

4. Quick Check:

   tone() on passive buzzer = beep at set frequency [OK]

Hint: tone() makes passive buzzer beep at given frequency [OK]

Common Mistakes:

• Thinking tone() works for active buzzers
• Assuming buzzer beeps once only
• Confusing frequency with volume

4. Identify the error in this Arduino code intended to make an active buzzer beep:

void setup() {
  pinMode(9, OUTPUT);
  tone(9, 500);
}
void loop() {}

medium

A. tone() cannot be used with active buzzers; use digitalWrite() instead.

B. pinMode() should be set to INPUT for buzzers.

C. The frequency 500 is too low for any buzzer to beep.

D. The loop() function must contain tone() to work.

Solution

1. Step 1: Check buzzer type and function used

   Active buzzers beep when powered on/off, so tone() is not suitable; digitalWrite() should be used.

2. Step 2: Identify correct control method

   Using tone() on active buzzer will not produce sound; digitalWrite(9, HIGH) turns it on.

3. Final Answer:

   tone() cannot be used with active buzzers; use digitalWrite() instead. -> Option A

4. Quick Check:

   Active buzzer needs digitalWrite(), not tone() [OK]

Hint: Use digitalWrite() for active buzzers, not tone() [OK]

Common Mistakes:

• Using tone() with active buzzer
• Setting pinMode to INPUT instead of OUTPUT
• Expecting loop() to be mandatory for tone()

5. You want to play a melody using an Arduino and a buzzer. Which buzzer type should you choose and why?

hard

A. Active buzzer, because it can play melodies with just power.

B. Passive buzzer, because it can produce different tones using signals.

C. Active buzzer, because it is louder and easier to control with tone().

D. Passive buzzer, because it works without any signal or code.

Solution

1. Step 1: Understand melody requirements

   Playing melodies requires changing tones/frequencies, which needs control signals.

2. Step 2: Match buzzer type to melody capability

   Passive buzzers can produce different tones using tone() function; active buzzers only beep on/off.

3. Final Answer:

   Passive buzzer, because it can produce different tones using signals. -> Option B

4. Quick Check:

   Melodies need passive buzzer with tone() control [OK]

Hint: Use passive buzzer for melodies; active only beeps [OK]

Common Mistakes:

• Choosing active buzzer for melodies
• Thinking active buzzers can change tone
• Assuming passive buzzers work without signals