A speedy messenger
that uses sound
for important notices.

Buzzers

LIBRARY

#11

Profile

Beep beep! Boop! I’m the part that makes sounds.
Machines need me to send signals.
Buzzers can only make set sounds. Speakers can change sounds, but they’re a whole other part.

The Power of Buzzers

The tricky one who sends signals with sound.

Buzzers are used in electrical devices, automobiles, and other familiar machines.
For example, the sounds from buttons, washing machines, and thermometers all tell us things.
Sometimes loud noises warn us of bad things.

An illustration of buzzers at work in machines: a microwave oven, thermometer, car, scale, and washing machine.

The Secret of the Power of Buzzers

Piezoelectric ceramic makes the noises!

The secret part of a buzzer that makes the noise is the “piezoelectric ceramic” inside it.
This is the part that vibrates when electricity flows through it. They make sound by making the air move when they do.

An illustration of the insides of a buzzer. There is a thin, round plate inside the case, which has a vibrating metal part around its edge. The center is piezoelectric ceramic. There are two rod-shaped electrodes that stick out of the case, pointing down. The piezoelectric ceramic makes sound by shaking the air when it shakes!

Friends of Buzzers

Various shapes of buzzers

Some buzzers are square, and others are round. They are made to fit the place where they will be used!

Trivia

What are the symbol and unit for buzzers?

We show the volume of sound with S.P.L. as a unit, and pitch of sound with frequency.
The unit for S.P.L. is “dB” (for “decibels”). The more dB, the louder the sound.
For frequency, the symbol is “Hz” (for “hertz”). The more Hz, the higher pitch the sound.
Humans can hear sounds in the range of 40 Hz to 20 kHz (kHz stands for kilohertz, a unit of 1000 Hz).

Think it out!

QUESTION

The answer is 3.
Number three was right, guitar sounds and piano sounds!
You need speakers to change the tone!

Find the Buzzer!