# Physics Quiz 1

The flashcards below were created by user stephaniefu on FreezingBlue Flashcards.

1. V = ?
V = F X W
2. Increase density = ?
Increase density = decrease velocity
3. Increase compressibility = ?
Increase compressibility = decrease velocity
4. Increase stiffness = ?
Increase stiffness = increase velocity
5. Pulse Repetition Frequency (PRF)
The number of pulses emitted per second

Unit: Hertz

Typical range: 1-10KHz
6. Pulse Repetition Period (PRP)
The time from the beginning of one pulse to the beginning of the next

Unit: Seconds

Time of producing and receiving echo
7. PRP = ?
PRP = 1/PRF
8. Pulse Duration (PD)
The time during which the pulse actually occurs

Unit: Seconds
9. PD = ?
• PD = number of cycles X period
• PD = number of cycles / Frequency
10. Duty Factor (DF)
The fraction of time the ultrasound pulse is being emitted during one pulse repetition period

The DF of Continuous Wave is 1(100%)

The DF of Pulse Wave is less than 1
11. DF = ?
DF = Pulse Duration/ Pulse Repetition Period
12. Spatial Pulse Length (SPL)
The length or space over which an ultrasound pulse occurs

Units : meter, mm

• Affects greatly of image resoultion
• -long SPL will interact with a tissue interface longer than a short SPL, which as blurred image
13. Near Field
Fresnel Zone

Closer to the transducer

Collimated beam
14. Far Field
Fraunhofer Zone

Farther to the transducer

Divergence of the beam
15. Beam Shape Parameter
Ultrasound frequency and transducer diameter affect the length of near field and divergence of far field

Increase frequency and transducer diameter = increase near field length and decrease divergence of far field
16. Increase Transducer diameter =
Increase Transducer diameter = (frequency is constant) length of near field increase and decrease far field divergence
 Author: stephaniefu ID: 193972 Card Set: Physics Quiz 1 Updated: 2013-01-20 22:25:23 Tags: Physics Quiz Folders: Description: Physics Quiz 1 Show Answers: