Topicm793880772cebfdfe_1528449000663_0Topic

Sound waves as an example of harmonic waves. Sound featuressound featuresSound features: pitch and sensation. The pitch of sound

Levelm793880772cebfdfe_1528449084556_0Level

Second

Core curriculumm793880772cebfdfe_1528449076687_0Core curriculum

VIII. Vibrating motion and waves. The student:

6) describes the mechanism of formation and propagation of sound waves in the air; gives examples of sound sources.

Timingm793880772cebfdfe_1528449068082_0Timing

45 minutes

General learning objectivesm793880772cebfdfe_1528449523725_0General learning objectives

Presenting sound waves and their properties.

Key competencesm793880772cebfdfe_1528449552113_0Key competences

1. Defining the concept of the sound wavesound wavesound wave.

2. Describing the propagation of an acoustic wave in the air.

3. Presenting the properties of sound waves.

Operational (detailed) goalsm793880772cebfdfe_1528450430307_0Operational (detailed) goals

The student:

- knows the mechanism of propagation of sound waves,

- is able to indicate the properties of the acoustic wave.

Methodsm793880772cebfdfe_1528449534267_0Methods

1. Problem lecture.

2. Formulating problems and ideas for solving them.

Forms of workm793880772cebfdfe_1528449514617_0Forms of work

1. Work in groups.

2. Making notes during the lesson.

Lesson stages

Introductionm793880772cebfdfe_1528450127855_0Introduction

Answer the introductory questions for the lesson:

1. What is the wave?

2. What is the propagation of the wave in a resilient mediumresilient mediumresilient medium?

3. List the basic quantities describing sound.

Procedurem793880772cebfdfe_1528446435040_0Procedure

Definition:

Sound waves are longitudinal mechanical waves. They can propagate either in solids or in liquids and gases. They propagate in a material medium as a sequence of vibrations of the medium particles.

The frequency range of mechanical waves can be very high. However, sound waves are only those waves that can be heard by the human ear. These are the waves in frequency range between 20 - 20000 Hz. It is called the „audible range”.

Waves with frequencies which are higher than the audible range are called ultrasounds, and the waves below the audible frequencies are called infrasounds.m793880772cebfdfe_1527752263647_0Sound waves are longitudinal mechanical waves. They can propagate either in solids or in liquids and gases. They propagate in a material medium as a sequence of vibrations of the medium particles.

The frequency range of mechanical waves can be very high. However, sound waves are only those waves that can be heard by the human ear. These are the waves in frequency range between 20 - 20000 Hz. It is called the „audible range”.

Waves with frequencies which are higher than the audible range are called ultrasounds, and the waves below the audible frequencies are called infrasounds.

[Slideshow]

Sound featuressound featuresSound features:

a) Pitch of sound - depends on the frequency of the acoustic wave, i.e. on the frequency of the sound source. A single frequency acoustic wave is called a tone.
b) Sound intensity - it is a property of auditory sensations that allows us to distinguish which sound is loud and which is quiet.
c) Timbre of sound - a sound characteristics that allows to distinguish the sound of different instruments or the human voice. The sound of each instrument is determined primarily by the method of sound production and the construction of the instrument.m793880772cebfdfe_1527752256679_0a) Pitch of sound - depends on the frequency of the acoustic wave, i.e. on the frequency of the sound source. A single frequency acoustic wave is called a tone.
b) Sound intensity - it is a property of auditory sensations that allows us to distinguish which sound is loud and which is quiet.
c) Timbre of sound - a sound characteristics that allows to distinguish the sound of different instruments or the human voice. The sound of each instrument is determined primarily by the method of sound production and the construction of the instrument.

Lesson summarym793880772cebfdfe_1528450119332_0Lesson summary

- Sounds are the waves created by vibrating bodies at the frequency within the range from 16 Hz to 20 kHz. This range is contractual; in fact it is an individual property of every person.

- The basic sound featuressound featuressound features are:

• pitch - associated with the wave frequency: higher sound - higher frequency,

• loudness - related to the amplitude of the wave: greater amplitude - louder sound,

• timbre - connected with the vibrational complexity of the wave source, allows to distinguish the sounds of different instruments.

Selected words and expressions used in the lesson plan

audible frequenciesaudible frequenciesaudible frequencies

auditory sensationsauditory sensationsauditory sensations

earearear

harmonic waveharmonic waveharmonic wave

longitudinal mechanical waveslongitudinal mechanical waveslongitudinal mechanical waves

pitch of the soundpitch of the soundpitch of the sound

resilient mediumresilient mediumresilient medium

sound featuressound featuressound features

sound wavesound wavesound wave

timbre of the soundtimbre of the soundtimbre of the sound