Concept explainers
(a)
The intensity reflection coefficient between transducer material and air.
Answer to Problem 76PE
The intensity reflection coefficient between transducer material and air is
Explanation of Solution
Given:
Refer Table [17.8]
The value of acoustic impedance of transducer material is,
The value of acoustic impedance of air is,
Formula used:
The intensity reflection coefficient betweenthe transducer material and air is given by
Calculation:
The intensity reflection coefficient between transducer material and air is calculated as follows:
Conclusion:
The intensity reflection coefficient between transducer material and air is
(b)
The intensity reflection coefficient between the transducer material and gel which is identical to water.
Answer to Problem 76PE
The intensity reflection coefficient between the transducer material and gel which is identical to water is
Explanation of Solution
Given:
Refer Table [17.8]
The value of acoustic impedance of gel which is identical to water is,
Formula used:
The intensity reflection coefficient between the transducer material and gel which is identical to water is given by
Calculation:
The intensity reflection coefficient between the transducer material and gel which is identical to water is calculated as follows:
Conclusion:
The intensity reflection coefficient between transducer material and gel which is identical to water is
(c)
The reason behind the use of gel.
Explanation of Solution
Introduction:
In a medical application, during ultrasound a transducer is used to emit the ultrasonic waves which enter into the body due to which high vibration are produced by the piezoelectric effect. The entered waves produce voltage pulses and are recorded for examination.
There is air between the transducer and the body, but during examination, the air is replaced by the gel. This is replaced due to the fact that the reflections also reduced with the air. The gel produces minimum reflection during ultrasound and produce accurate result.
Conclusion:
The gel is used to minimize the reflections.
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Chapter 17 Solutions
College Physics
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