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What does it mean that sound is a mechanical wave?
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Being a mechanical wave means that sound requires a medium to propagate; it cannot travel through a vacuum.
What happens during the compression and rarefaction phases of a sound wave?
During compression, the particles experience high density and high pressure. During rarefaction, the particles experience low density and low pressure.
How are sinusoidal waves used to represent sound waves?
Sinusoidal waves represent sound waves through peaks that indicate compressions and troughs that indicate rarefactions.
What are the five key characteristics of sound?
1. Sound is a wave that carries energy 2. Sound is a mechanical wave 3. Sound is a longitudinal wave 4. Sound travels in a straight line 5. Sound cannot travel through a vacuum
How does an ultrasound machine use high-frequency waves to create images?
The machine sends out a high-frequency wave, the acoustic energy in the wave is transferred into the patient, and then the energy is transferred back to the machine to create images.
What is a mechanical wave, and can you give some examples?
A mechanical wave requires a medium to propagate. Examples include sound, ropes, springs, seismic activity, and water.
What are the study areas in ultrasound?
The study areas in ultrasound include acoustic propagation properties (how the body affects the wave) and biological effects/bio effects (how the energy affects biological tissue).
What is a special case of destructive interference?
If two waves of the same strength and frequency are 180 degrees out of phase, they cancel each other out completely.
How do constructive and destructive interference of sound waves differ?
Constructive interference occurs when two waves in phase add together to make a larger wave. Destructive interference occurs when two waves out of phase subtract from one another, making the new wave smaller.
List the seven acoustic parameters of sound waves.
1. Frequency 2. Period 3. Wavelength 4. Amplitude 5. Power 6. Intensity 7. Propagation Speed
Define acoustic propagation properties in the context of ultrasound.
Acoustic propagation properties refer to how the body affects the ultrasound wave as it travels through it.
Explain the term 'bio effects' in ultrasound.
'Bio effects' refer to how the energy from the ultrasound wave affects biological tissue within the body.
What is the difference between mechanical and electromagnetic waves?
Mechanical waves need a medium to travel through, while electromagnetic waves can travel through a vacuum or a medium.
What are the three key acoustic variables in sound waves, and how are they measured?
Pressure (measured in Pascals), density (measured in kg/cm³), and particle motion (distance measured in units like cm, mm, ft, or miles).
What are transverse and longitudinal waves, and how do they differ?
Transverse waves have particles that move perpendicular to the wave direction (e.g., ocean waves), while longitudinal waves have particles that move parallel to the wave direction (e.g., sound waves).
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