Physical fundamentals of acoustics. (1980)

The ruins of the ancient Roman theater.

Bell ringing.

The organ sounds.

A man strikes a tuning fork.

A cartoon that uses the example of a tuning fork to explain the wave nature of sound.

Waves on the water.

The experience of the passage of sound waves in a liquid is shown.

The nature of the waves arising depends on the elastic properties of the medium.

There are longitudinal and transverse waves.

The main physical characteristics of sound are frequency, intensity, sound pressure and spectral composition.

Determination of the intensity or strength of the sound.

The formula for the power of sound.

Definition of the concept of sound pressure.

The formula of the sound pressure amplitude.

Determination of sound intensity.

The formula of sound intensity.

A cartoon explaining the sensation of sound by a person, audible waves, infrasound, ultrasound.

Experience in the interference of sound waves.

The essence of the interference of sound waves.

Experience in the distribution of the amplitudes of standing waves.

Standing sound waves largely determine the nature of the sound of musical instruments.

The musician plays the guitar.

By pressing the strings, the musician adjusts the length of the standing wave, i.e. the frequency of the sound.

The pianist plays the piano.

The acoustics of the hall depends on the system of standing waves generated in the room.

The simplest example of periodic sound waves are sine waves.

The musician holds the bow on the tuning fork.

A cartoon explaining the concept of purity of tone.

The concept of elastic waves.

There are two main groups of sounds: tonal or musical and noises.

In tonal sounds, you can always find a set of harmonic combinations.

Recording noises on the streets of the city.

Noises are caused by such processes in which the purity and amplitude of the sound does not have stable forms.

Experiment to determine the spectrum of audible sounds based on resonance.

Currently, more advanced electroacoustic methods of sound analysis are used.

The principle of operation of the electroacoustic method.

Even more perfect is the analysis of the sound spectrum using a computer.

The musician plays the guitar.

The concept of sound.

Physical and physiological concepts of sound.

Physiological characteristics of sound: height; timbre; volume.

The influence of purity on the perception of pitch.

Experience with the savar siren device.

The physiological coloration of the sound is created by overtones.

The sound engineer's remote control.

A cartoon explaining the area of audibility of sound.

The concept of sound pressure.

The sound pressure formula.

Explosion.

A cartoon telling about low-frequency elastic waves.

The concept of the voice of the sea.

Dolphins in a scientific laboratory at sea.

Ultrasound in nature.

Bats and dolphins use ultrasound in echolocation.

Dolphins use ultrasound to communicate with each other.

Ultrasound is actively used in industry.

The principle of operation of echo sounders and depth gauges.

Echo sounders and depth gauges on the bridge on the ship.

A cartoon telling about the principle of ultrasonic flaw detection.

An ultrasonic flaw detector installed on an automatic pipe production line allows continuous monitoring of the wall thickness.

Any deviation is recorded on the device.

Experience in creating crushing properties of ultrasound in liquid.

The surface of the emitter after the experiment.

Today, cavitation is used to clean parts.

High-power ultrasound allows mechanical processing of materials with high hardness.

In this case, there is a liquid with a fine abrasive between the emitter and the workpiece.

Samples of parts processed in a similar way.

With the help of ultrasound, it is possible to obtain holes of a wide variety of configurations.

Machines on which plastic is welded by ultrasound.

A musician plays the organ.