Define doppler effect
the shift in received frequency due to the motion of a vibrating source toward or away from a receiver.
Define doppler shift
the change in numbers of cycles received per unit of time.
Define beat frequency
a series of alternate reinforcements and cancellations produced by the interference of two waves of slightly differing frequencies, heard as a throbbing effect in sound waves.
Define sound
Sound is a mechanical wave that carries energy from one location to another by mechanical energy. it is a pressure disturbance traveling through a medium.
Define refraction
a bending of sound or any wave caused by a difference in wave speeds.
Define energy wave absorption
is the transferring of wave energy to the medium through which it is moving.
Define reflaction
the portion of sound the is not absorbed into a media but bounces off (echo)
Define natural frequency
the frequency at which an elastic object tends to vibrate when it is disturbed and the disturbing force is removed.
Define resonance
The response of a body when a forcing frequency matches its natural frequency.
Define intensity
the power per square meter carries by a sound wave, measured in decibels.
Define periodic sound waves.
when the sound of an object continues to vibrate with periodic motion creating repetitions of the distance. The frequency of the repetitions equals the frequency of the originating vibration. The repetition has the same frequency and wavelength in the med
Explain how the frequency and wavelength of a periodic disturbance are altered if the source of the disturbance is moving.
if the source of the disturbance is moving, the pattern of sound waves is distorted and no longer made of concentric circles. The center of the waves moves in the direction that the source is moving. The observer would measure the wavelengths as more freq
Outline the doppler effect
if the source of the disturbance is moving, the pattern of sound waves is distorted and no longer made of concentric circles. The center of the waves moves in the direction that the source is moving. The observer that the disturbance is moving towards wou
Explain how the magnitude and direction of frequency change of the doppler effect indicates the direction and speed of the moving wave source.
Whenever there is relative motions between the sender and receiver of sound, the change in relative positions causes a change in the number of cycles received per time (change in frequency) (termed the doppler shift frequency). The net frequency that the
Explain how, for sound waves, the doppler effect holds if either the sender or receiver of the sound waves is moving.
Whenever there is relative motions between the sender and receiver of sound, there is a frequency shift in the sound.
Explain why sound can be described as a pressure wave.
the pressure disturbance is a series of localized increased particle density and lower particle density.
Explain how sound is propagated and moved though a medium.
sound originates from the vibration of an object that disturbs the medium surrounding it. The pressure wave moves as a chain reaction form particle to adjacent particle.
Explain what determines the frequency of a sound wave that is emitted form a source.
the frequency of the sound wave is determined by the vibration of the source producing the pressure wave.
Relate the velocity of sound in a medium to the density and stiffness of the medium.
as sound passes through a medium, the velocity of sound will change . Material with high density and elastic properties tend allow the energy to transmit with little loss as the atoms are relatively close together and respond quickly to one anther's motio
Outline the processes of reflection and refraction of a sound wave at an interface between two media.
as sound hits the interface between 2 media, less than 100% of sound is transmitted into the new media. a proportion is reflected (echo). the amount of reflection depends on how different the two materials are in their ability to transmit sound. The smoot
Outline the process of sound absorption.
As sound is a pressure wave, it exerts force/area.
Outline the concept of resonance of an object.
each object tends to vibrate at a specific frequency when a pulse for energy is added to it to set it in motion. the frequency of vibration depends on the object's dimensions, tension and mass. When the frequency of incoming pulsed energy matches the natu
discuss the energy and power of a sound wave.
the energy (intensity) of a wave is the quantity of energy per unit of time passing through an area that is perpendicular to the waves propagation. the greater the intensity of the sound wave, the greater the displacement of the particles by the wave (> e
Relate the amplitude of a sound wave to the intensity of the wave.
as the amplitude increase, the intensity of the sound wave increases.
Explain the use of the decibel to compare sound intensities.
since sound covers a large range, a logarithic scale is used to compresses values into a smaller range. Intensity levels are relative to the base level which is considered the threshold for normal hearing. a power increase of 10 relative to the baseline i
Discuss clinical applications of waves and sound.
ultrasound imaging - send in sound waves of specific frequency into body tissues causing echos at the interface of different tissues. The echoes are captured and measured (quantity of echo determines the nature of the tissue and the delay indicates the de