Ultrasound physics Chapter 2 review

Which of the following bests describes ultrasound?

A mechanical vibration transmitted through a medium in the form of a wave

Sound is best described as _____.

A series of compressions and rarefactions

If waves are in-phase, their peaks occur

At the same tine

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

Bulk modulus of the medium

Units of distance is:

Cm, ft, miles

An area of high pressure and particle density on a pressure wave is referred to as a ____.

Compression

On a diagram of a waveform, the peak above the baseline represents

Compression

Positive amplitude of wave, an area of high pressure and particle density on a pressure wave is referred to as a:

Compression

The highest level of concentration of molecules in a wave is called

Compression

When waves of different frequencies interfere:

Constructive and destructive interference may occur

Interaction of echoes that causes reinforcement rather than cancellation is known as:

Constructive interference

What happens when two in-phase waves meet?

Constructive interference

When waves combine to form a single wave of less amplitude, it is called

Constructive interference

------------one compression and one rarefaction

Cycle

—— is concentration of mass within a volume.

Density

What happens when two out-of-phase waves meet?

Destructive interference

Sound waves carry ____ along their path.

Energy

Sound waves can go through a vacuum if the amplification is high enough.

False

Constructive interference has the effect of ____ the amplitude of a wave.

Increasing

Which of the following describes the sound wave phenomenon displayed in the image?

Interference

Units of density is:

Kg/cm3

The term compression zone describes a region of ____ in the medium, which is subjected to an ultrasound field.

Low pressure

Density is defined as

Mass per unit of volume

In a longitudinal wave the sound beam runs parallel or perpendicular to the direction of particle motion?

Parallel

Unit for pressure is?

Pascal (Pa)

In a transverse wave the sound beam runs parallel or perpendicular to the direction of particle motion?

Perpendicular

Which of the following are acoustic variables?

Pressure, motion of particles in the wave, density

An area of low pressure and particle density on a pressure wave is referred to as a ____.

Rarefaction

Negative amplitude of wave, an area of low pressure and particle density on a pressure wave is referred to as a:

Rarefaction

Which best describes sound waves?

Series of compressions and rarefactions

Which of the following types of waves require a medium in order to propagate?

Sound

All of the following statements are true regarding sound waves, except:

They are longitudinal, electromagnetic waves.

Sound is a mechanical longitudinal wave

True

Which of the following terms does not belong with the others?

Wider molecular spacing

As sound travels through a medium, what term describes the effects of the medium on the sound wave?

acoustic propagation properties

What are rarefactions?

areas of decreased pressure & density(regions of lower density & pressure)

What are compressions?

areas of increased pressure and density

Define pressure:

concentration of force within an area

Sound can be characterized as:

cyclical oscillations in certain variables

—— measure of particle motion

distance

What is the formula for pressure?

force/area

A particle within a transverse wave is traveling vertically. What is the direction of the wave's propagation?

horizontal

Two waves arrive at a location at the same time. What event takes place?

interference

Waves that exist at the same location and time will combine together. What is this called?

interference

When particle motion of a medium is parallel to the direction of a wave propagation, what is the wave being transmitted called?

longitudinal wave

Which of the following describes the characteristics of a sound wave?

mechanical, longitudinal

The acoustic variables are:

pressure, density, distance

All of the following are true about sound waves except:

they are transverse

Particles moving in a perpendicular direction (right angles or 90degrees) to the direction of the wave is called:

transverse wave

The direction of motion of a particle in a wave is perpendicular to the direction of propagation of the wave. What type of wave is this?

transverse wave