Nature Of Sound

Question 1

It is a travelling variation in one or more quantities such as pressure. It is produced by something moving back and forth or vibrating.

Answer 1

Wave

Question 2

What is the relationship of frequency to sound absorption?

Answer 2

Higher frequencies are absorbed more rapidly than lower frequencies.

Yet lower frequencies have better penetration.

Question 4

It can be transmitted and produced by matter and can travel only in matter.

Answer 4

Mechanical wave

Question 6

Motion of the particles in a medium PARALLEL to the direction of the wave propagation.

Answer 6

Longitudinal

Question 7

Motion of the particle in the medium is PERPENDICULAR to the wave propagation.

Answer 7

Transverse wave

Question 8

What is the relationship of the frequencies to spatial resolution?

Answer 8

Higher frequencies have shorter wavelength. Shorter wavelength can distinguish between reflectors thatbaremcloser together. Therefore, higher frequencies have better spatial resolution but limited penetration.

Question 9

As the frequency of the UTZ increases:

The penetrability of the beam _____

Answer 9

Decreases

Question 10

As the frequency of the UTZ increases:

The beam becomes _____

Answer 10

More colimated and directional

Question 12

Distance between two consecutive identical positions in the wave.

Answer 12

Wavelength

Question 13

The time it takes for one cycle to occur.

Answer 13

Period

Question 14

Occurs when ultrasound waves of the different frequency are out of phase

Answer 14

Destructive Interference

Question 15

Medical imaging that uses nonionizing, high frequency sound waves to generate image of a particular structure.

Answer 15

Sonography

Question 16

As the frequency of the UTZ increases:

The ability to resolve small objects ________

Answer 16

Improves, increases

Question 17

Relationship of period and frequency

Answer 17

Inversely related

Question 18

Refers to the relationship of one wave to the other

Answer 18

Phase

Question 19

It can travel either through matter or through empty space

Answer 19

Electromagnetic wave

Question 20

Waves whose wavefronts are at the SAME position

Answer 20

In phase

Question 21

It is the length of the space that a pulse takes up

Answer 21

Spatial Pulse Length

Question 22

Waves whose wavefronts are at the DIFFERENT position

Answer 22

Out of phase

Question 23

Sound is an energy transmitted as a ___________, __________ wave that requires a medium through which to travel.

Answer 23

Mechanical, longitudinal

Question 24

What will be the result if ultrasound waves of the same frequency are in phase?

Answer 24

Imcreased amplitude

Increased intensity of the beam

Question 25

What will be the result if ultrasound waves of the same frequency are out of phase?

Answer 25

Decreased amplitude

And it contributes to ultrasound attenuation

Question 26

Fraction of the time that pulsed ultrasound is on

Answer 26

Duty Factor

Question 27

It is the interaction if two or more ultrasound beams having different frequency and/or phase.

Answer 27

Interference

Question 28

Points of zero amplitude caused by destructive interference.

Answer 28

Nodes

Question 30

Types of ultrasound wave used in diagnostic equipments in which cycles repeat indefinitely

Answer 30

Continuous wave

Question 31

No. of cycles per second performed by the particles in the medium in response toma wave passing through it

Answer 31

Frequency

Question 33

It is the time from the beginning of one pulse to the next

Answer 33

Pulse Repitition Period

Question 34

Two waves traveling in the opposite directions with the sample amplitude interfere and create a?

Answer 34

Standing waves

Question 36

Points of maximum amplitude caused by constructive interference

Answer 36

Antinodes

Question 37

It is the number of pulses occuring in one sec.

Answer 37

Pulsed Repition Frequency (PRF)

Question 38

It is said that every point on a wave-front may be comsidered a source of secondary spherical wavelets which spread out in the forward direction at the speed of light. The new wave-front is the tangetial surface to all these secondary wavelets.

Answer 38

Huygens' Principle

Question 39

It is the time it takes for one pulse to occur

Answer 39

Pulse Duration

Question 40

Occurs when ultrasound waves of the same frequency are in phase

Answer 40

Constructive Interference

Question 41

Types of ultrasound wave used in diagnostic equipments in which it consists pulses separated by gaps in time

Answer 41

Pulsed

Question 42

2 types of ultrasound waves used in diagnostic equipments

Answer 42

Continuous and pulsed

Question 44

When two sound waves with slightly different frequencies combine.

Answer 44

Beat frequency