Physics 1 Final Part 1

Front 1

What is the speed of sound in soft tissue?

Back 1

1540 m/s

Front 2

Sound waves can be described best as...

Back 2

Mechanical and longitudinal

Front 3

1 MHz is how many cycles per second?

Back 3

1 million cycles per second

Front 4

10,000 m is how many km

Back 4

10 km

Front 5

The effects of the sound wave upon the biologic tissue through which it passes is called?

Back 5

Biologic effects

Front 6

What are the acoustic variables?

Back 6

Pressure, density, and distance

Front 7

As frequency increases, propagation speed decreases.

Back 7

False

Front 8

Frequency of audible sound

Back 8

20 Hz and 20,000Hz

Front 9

True or False: Lower numerical values of axial resolution indicates a shorter pulse, creating a more accurate image.

Back 9

True

Front 10

Wavelength is determined by...

Back 10

Sound source and medium

Front 11

Propagation speed is determined by...

Back 11

Medium

Front 12

How are Pulse repetition periods (PRP) and Pulse repetition frequency (PRF) related?

Back 12

Inversely related to each other

Front 13

What are the 7 acoustic parameters

Back 13

Frequency, period, wavelength, speed, intensity, amplitude,and power

Front 14

What is the concentration of the energy in a sound beam?

Back 14

Intensity

Front 15

Sound moving in decreased pressure and density is called

Back 15

Rarefactions

Front 16

For each cm of reflector depth in soft tissue how many microseconds is the time of flight?

Back 16

13 microseconds

Front 17

The time of flight is ____ related to the depth

Back 17

Directly

Front 18

The most relevant intensity with respect to tissue heating...

Back 18

SPTA

Front 19

T or F: 26 microseconds= 4 cm total distance traveled

Back 19

True

Front 20

Whatever percentage remains must be the intensity transmission coefficient. There must be what kind of energy at the boundary?

Back 20

Conservation of energy

Front 21

T or F: US penetrates further with lower frequency

Back 21

True

Front 22

Sound waves weakens as they propagate in a medium. This decrease in intensity, power, and amplitude as sound travels is called...

Back 22

Attenuation

Front 23

What are the units that all intensities have?

Back 23

W/cm²

Front 24

What are the two bio effects?

Back 24

Heat and cavitation

Front 25

A reduction in the intensity of a sound beam to one quarter of its original value is how many dB?

Back 25

-6 dB

Front 26

Advantage of describing sound weakening with an attenuation coefficient is that it's value ____ _____, regardless how far it travels

Back 26

Remains constant

Front 27

is the change in directions of a wave propagation when traveling from one medium to another.

Back 27

Refraction