ARDMS SPI Exam - Topic 3 Question 20 Discussion

Actual exam question for ARDMS's SPI exam

Question #: 20
Topic #: 3

[All SPI Questions]

What determines the resonant frequency of a pulsed wave transducer?

AElement thickness and pulse repetition frequency

BElement diameter and speed of sound in element

CElement diameter and element thickness

DElement thickness and speed of sound in element

Show Suggested Answer

Suggested Answer: D

The resonant frequency of a pulsed wave transducer is determined by the thickness of the piezoelectric element and the speed of sound within that element. The resonant frequency is inversely proportional to the element thickness and directly proportional to the speed of sound in the material. Thinner elements and higher sound speeds result in higher resonant frequencies, while thicker elements and lower sound speeds result in lower resonant frequencies. Reference:

ARDMS Sonography Principles and Instrumentation guidelines

Kremkau, F. W. (2015). Diagnostic Ultrasound: Principles and Instruments. Elsevier.

by Nilsa at Jan 05, 2026, 05:16 AM

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Maryln

3 days ago

Hmm, I'm not sure about this one. Maybe B? Element diameter and speed of sound in element?

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Stephaine

8 days ago

C. Element diameter and element thickness seems like the right choice to me.

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Marsha

13 days ago

I think the answer is D. Element thickness and speed of sound in element.

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Carey

18 days ago

I feel like the answer has to do with both thickness and diameter, but I’m confused about how they interact with the speed of sound.

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Nan

23 days ago

I practiced a similar question where element thickness was mentioned, but I can't remember if speed of sound was included in that one.

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Trinidad

29 days ago

I remember something about element diameter affecting the frequency, but I can't recall if it was just that or if thickness plays a role too.

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Edmond

1 month ago

I think the resonant frequency is influenced by the element thickness, but I'm not sure about the other factors.

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Lon

1 month ago

I'm pretty confident it's D. The thickness and speed of sound in the material are the key factors that set the resonant frequency. Gotta remember that for the exam.

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Rosann

1 month ago

Ugh, I hate these transducer questions. The formulas always get me mixed up. I'm just gonna guess and hope for the best.

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Garry

2 months ago

Okay, I've got this. The resonant frequency is all about the properties of the transducer element itself, not the pulse repetition. So it's gotta be either C or D.

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Jonelle

2 months ago

Hmm, I'm not sure about this one. I'll need to think it through carefully. Maybe I can eliminate some of the options first.

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Kasandra

2 months ago

I think it's D. The element thickness and speed of sound in the element should determine the resonant frequency.

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