Exam 1

Question 1

Which pulse has a longer wavelength?

Answer 1

from a 2 MHz probe

Question 2

Sound propagates faster in media (materials) with greater

Answer 2

Stiffness

Question 3

Sound can be described as

Answer 3

Cyclical oscillations within a set of variables (A wave is the rhythmical variation throughout time)

Question 4

Which pulse has the lower propagation speed?
2mHz or 10 mhz probe

Answer 4

they are the same

Question 5

Which statement is true considering the propagation speed of sound through air?

Answer 5

Propagation speed in air is slower than in soft tissue

Question 6

Image quality is affected by wavelength?

Answer 6

True

Question 7

Intensity can be changed by the sonographer.

Answer 7

True

Question 8

If stiffness increases, propagation speed

Answer 8

Increases

Question 9

The frequency of a transducer is 25,000,000 cycles per second. This can be written as

Answer 9

25 MHz

Question 10

If the power of a wave is halved, the intensity is reduced to 1/4 its value.

Answer 10

False

Question 11

Which of the following applies to sound waves less than 20 Hz compared to sound waves greater than 20 Hz?

Answer 11

They have less attenuation

Question 12

Which waves are audible?

Answer 12

28 Hz

Question 13

If beam area is reduced by half and the power stays the same, the intensity

Answer 13

Doubles

Question 14

If both propagation speed and frequency double, the wavelength will

Answer 14

Remain the same

Question 15

Which parameter of the medium has the most effect on the velocity of sound in that medium?

Answer 15

Bulk modulus of the medium

Question 16

Shorter wavelengths create higher quality images with better detail.

Answer 16

True

Question 17

If the amplitude is doubled, the intensity is

Answer 17

Increased 4 times

Question 18

If a sound wave of 2 MHz is traveling through soft tissue, what is the wavelength?

Answer 18

0.77mm

Question 19

With a 2 MHz transducer, the wavelength in soft tissue is approximately

Answer 19

0.75mm

Question 20

The highest speed of sound is through which body structure?

Answer 20

Bone

Question 21

Wavelength is equal to the propagation speed

Answer 21

Divided by frequency

Question 22

The wavelength of the 3MHz transducer is shorter than the 6 MHz transducer

Answer 22

False

Question 23

A bouquet has 30 flowers. The size of the bouquet is decreased by a factor of 3. How many flowers remain?

Answer 23

10

Question 24

The propagation speed used for soft tissue is

Answer 24

An average based on the usual percentages of each type of tissue

Question 25

When the elasticity of a medium is high, the _________ is high.

Answer 25

Compressibility

Question 26

The normal range of intensities used in Doppler ultrasound is

Answer 26

0.2 to 400 W/cm squared

Question 27

Which statement is correct regarding sound travel through a medium?

Answer 27

The molecules oscillate (vibrate) back and forth to create and transmit the sound wave

Question 28

What term is the reciprocal of Mega?

Answer 28

Micro

Question 29

Propagation speed = ______________ X wavelength

Answer 29

Frequency

Question 30

All of the following are acoustic parameters except

Answer 30

Pressure

Question 31

The units label used for power is

Answer 31

Watts

Question 32

All of the following are true of sound waves except

Answer 32

They are transverse

Question 33

Which of the following will create the fastest speed of sound?

Answer 33

Low density, high stiffness

Question 34

Sound waves are

Answer 34

Longitudinal, mechanical

Question 35

If frequency increases, wavelength

Answer 35

Decreases

Question 36

The unit of measurement for wave frequency is a measurement of

Answer 36

Number

Question 37

The ultrasound wave travels faster than the audible wave.

Answer 37

False

Question 38

Which is a definition of period?

Answer 38

The time for one complete cycle to occur

Question 39

U/S travels slowest through

Answer 39

Lung

Question 40

If the frequency of an U/S wave is doubled, what happens to the period?

Answer 40

Halves

Question 41

What is the reciprocal of 5?

Answer 41

1/5

Question 42

The maximum cyclical change in a quantity is known as

Answer 42

Amplitude

Question 43

Two quantities are directly proportional if an increase in one quality leads to a/an _________ in the other.

Answer 43

Increase

Question 44

Which of following waves has the longest period?

Answer 44

6 hz

Question 45

If the power in a beam is 1 watt and the area is 5cm2, the beam’s intensity is

Answer 45

0.2 W/cm2