What is produced when a substance/material vibrates?
Sound is produced
Sound is the result of the vibration of particles in a medium, causing them to collide with nearby particles.
What is the motion of particles in a sound wave?
Longitudinal wave-like motion
Particles move in a longitudinal direction, spreading out in ripples from the source.
How does sound transfer energy?
Through repetitive longitudinal waves colliding particles
Sound transfers kinetic energy through various mediums.
Define a sound wave.
The movement of alternating compressions and rarefactions in a repetitive wave-like motion
Sound waves travel in a ripple motion away from the source.
What are compressions in a sound wave?
The part of a sound wave where the molecules are in high density
This occurs when particles are closely packed together.
What are rarefactions in a sound wave?
The part of a sound wave where molecules are low density
Rarefactions occur when particles are spread out.
How does the speed of sound vary by medium?
Sound travels faster through denser materials
Sound travels faster in solids than in liquids and gases.
What effect does temperature have on the speed of sound?
Particles in warmer materials vibrate faster
This leads to an increase in sound transmission speed.
What is a transverse wave?
A wave in which the medium vibrates at right angles to the direction of its propagation
Sound waves are not transverse.
Differentiate between transverse waves and longitudinal waves.
Transverse wave: Medium moves perpendicular to wave direction. Longitudinal wave: Medium moves parallel to wave direction
Examples of transverse waves include light waves; sound waves are longitudinal.
What is wavelength?
The distance between two successive waves
Wavelength is typically measured in meters (m).
Define frequency.
The number of waves per second measured in hertz (Hz)
Higher frequency waves correspond to shorter wavelengths.
What is pitch?
The degree of highness or lowness of a tone, directly proportional to frequency
High frequency results in high pitch.
What is amplitude?
The distance between particles in areas of compression
It is also described as the height of the peaks in a sound wave.
How is volume defined in terms of sound waves?
The loudness of a sound wave, directly proportional to the amplitude
Higher amplitude results in louder sounds.
What are the three ways sound is transmitted?
- Transmission
- Reflection
- Absorption
Each method describes how sound interacts with different materials.
How is sound reflected?
Reflected by hard, dense surfaces creating an echo
Examples include concrete or bathroom tiles.
How can noise be absorbed?
By soft (less dense) materials reducing reverberation
An example is curtain fabric.
What is an example of a string instrument that can adjust frequency?
Guitar, violin, piano
The length of the string affects the frequency of the sound produced.
What is a didgeridoo?
A wooden brass instrument traditionally used by the First Nations Peoples
Its sound is produced through vibrations and varies with the length of the instrument.
What is a cochlear implant?
An electronic device which stimulates auditory nerves through electrodes placed in the inner ear
Invented by Graeme Clark.
True or False: Sound waves are transverse waves.
False
Sound waves are classified as longitudinal waves.
Fill in the blank: A wave in which the medium vibrates at right angles to the direction of its propagation is called a _______.
Transverse wave
