Medical Physics : Sound, Hearing and Ultrasound Flashcards
What equation describes the pressure amplitude of a sound wave?
What equation describes the medium velocity of a sound wave?
How are the pressure and medium velocity of a wave related?
What is the intensity of a sound wave and how can it be calculated?
How do you calculate the speed of sound in a fluid?
How do you calculate the speed of sound in a gas?
What are the conditions for open and close pipe ends?
At closed end - there must be a node
At open end - there must be an antinode
What formula defines the frequency of a wave on a string?
What formula shows how much of a wave is transmitted.
What formula shows how much of a wave is reflected?
What formula describes the intensity level in dB?
What is A-mode ultrasound scanning?
This is amplitude mode where the echo intensity at each position is represented using a grey-scale.
What is M-mode ultrasound scanning?
Motion mode : The beam is fixed in position and changes the time of echo arrival are used to monitor movement of interfaces.
What conditions are there for T, the time it takes to record all the echos at one beam position
T>2L/v
To ensure that the echo from the deepest structure is detected before the next pulse is applied
What conditions are there for PRF (Pulse Repitition Frequency)
PRF<v>
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How is the intensity of sound attenuated through a tissue?
What formula describes the relative frequency change due to the doppler effect?
