PHYSICAL AGENTS PRACTICE
QUESTIONS EXAM 3 2025 QUESTIONS
AND ANSWERS
What two conditions are necessary for current to flow? (CH 11)
A. An energy source that creates a difference in electrical potential and a conductor
B.Current and ions
C. Current and a conductor
D. An energy source that creates a difference in electrical potential and a capacitor - ANS A.
An energy source that creates a difference in electrical potential and a conductor
Which of the following definitions best describes alternating current? (CH 11)
A. The unidirectional uninterrupted flow of charged particles with a duration of at least 1
second
B. The bidirectional uninterrupted flow of charged particles changing direction at least once per
second
C. The unidirectional or bidirectional flow of charged particles periodically ceasing for less than
1 second before the next electrical event
D. A monophasic pulse that randomly changes phase at least twice within 1 minute - ANS B.
The bidirectional uninterrupted flow of charged particles changing direction at least once per
second
Which type of waveform is most likely to produce a net charge in the underlying tissue? (CH 11)
A. An unbalanced waveform
B. A balanced waveform
C. A symmetrical waveform
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, D.An asymmetrical waveform - ANS A. An unbalanced waveform
What is the advantage of a carrier frequency? (CH 11)
A. It is more comfortable for patients and overcomes skin resistance easily.
B. It is more readily available than not having a carrier frequency.
C. It is delivered to the patient in a low frequency current.
D. There is no advantage - ANS A. It is more comfortable for patients and overcomes skin
resistance easily.
What does tissue hydration have on the impedance value of the skin? (CH 11)
A.Lower hydration results in no change in impedance.
B. Higher hydration results in higher impedance.
C. Higher hydration results in reduced impedance.
D. Lower hydration results in reduced impedance. - ANS C. Higher hydration results in
reduced impedance.
What chemical reaction takes place at the interface between the positive electrode and
underlying tissue? (CH 11.5)
A. The formation of hydrochloric acid, which softens tissues
B. The formation of sodium hydroxide, which softens tissues
C. The formation of hydrochloric acid, which hardens tissues
D. The formation of sodium hydroxide, which hardens tissues - ANS C. The formation of
hydrochloric acid, which hardens tissues
Which of the following definitions best describes direct current?
A. The unidirectional uninterrupted flow of charged particles with a duration of at least 1
second
B. The bidirectional uninterrupted flow of charged particles changing direction at least once per
second
C. The unidirectional or bidirectional flow of charged particles periodically ceasing for less than
1 second before the next electrical event
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QUESTIONS EXAM 3 2025 QUESTIONS
AND ANSWERS
What two conditions are necessary for current to flow? (CH 11)
A. An energy source that creates a difference in electrical potential and a conductor
B.Current and ions
C. Current and a conductor
D. An energy source that creates a difference in electrical potential and a capacitor - ANS A.
An energy source that creates a difference in electrical potential and a conductor
Which of the following definitions best describes alternating current? (CH 11)
A. The unidirectional uninterrupted flow of charged particles with a duration of at least 1
second
B. The bidirectional uninterrupted flow of charged particles changing direction at least once per
second
C. The unidirectional or bidirectional flow of charged particles periodically ceasing for less than
1 second before the next electrical event
D. A monophasic pulse that randomly changes phase at least twice within 1 minute - ANS B.
The bidirectional uninterrupted flow of charged particles changing direction at least once per
second
Which type of waveform is most likely to produce a net charge in the underlying tissue? (CH 11)
A. An unbalanced waveform
B. A balanced waveform
C. A symmetrical waveform
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, D.An asymmetrical waveform - ANS A. An unbalanced waveform
What is the advantage of a carrier frequency? (CH 11)
A. It is more comfortable for patients and overcomes skin resistance easily.
B. It is more readily available than not having a carrier frequency.
C. It is delivered to the patient in a low frequency current.
D. There is no advantage - ANS A. It is more comfortable for patients and overcomes skin
resistance easily.
What does tissue hydration have on the impedance value of the skin? (CH 11)
A.Lower hydration results in no change in impedance.
B. Higher hydration results in higher impedance.
C. Higher hydration results in reduced impedance.
D. Lower hydration results in reduced impedance. - ANS C. Higher hydration results in
reduced impedance.
What chemical reaction takes place at the interface between the positive electrode and
underlying tissue? (CH 11.5)
A. The formation of hydrochloric acid, which softens tissues
B. The formation of sodium hydroxide, which softens tissues
C. The formation of hydrochloric acid, which hardens tissues
D. The formation of sodium hydroxide, which hardens tissues - ANS C. The formation of
hydrochloric acid, which hardens tissues
Which of the following definitions best describes direct current?
A. The unidirectional uninterrupted flow of charged particles with a duration of at least 1
second
B. The bidirectional uninterrupted flow of charged particles changing direction at least once per
second
C. The unidirectional or bidirectional flow of charged particles periodically ceasing for less than
1 second before the next electrical event
2 Copyright ©BRIGHSTARS ALL RIGHTS RESERVED 2025
