NHA EKG TECHNICIAN (CET)
PRACTICE EXAM QUESTIONS AND
ANSWERS
1. Where is the electrode for lead V4 placed?
A. Fourth intercostal space, right sternal border
B. Fifth intercostal space, left anterior axillary line
C. Fifth intercostal space, left midclavicular line
D. Fourth intercostal space, left sternal border
Answer: C
Conceptual Explanation: Lead V4 is placed at the 5th intercostal space at the left
midclavicular line. A is V1, D is V2, and C is V5.
2. What is the standard gain setting for an EKG machine?
A. 5 mm/mV
B. 25 mm/mV
C. 20 mm/mV
D. 10 mm/mV
,Answer: D
Conceptual Explanation: The standard gain or sensitivity setting for an EKG is 10
mm/mV. 25 mm/sec is the standard paper speed.
3. A technician notes a rhythm with a PR interval of 0.24 seconds. Which of the following is
the most likely diagnosis?
A. Third-degree heart block
B. Second-degree Type I block
C. First-degree AV block
D. Normal sinus rhythm
Answer: C
Conceptual Explanation: A PR interval greater than 0.20 seconds indicates a first-degree
AV block, representing a delay in conduction from the atria to the ventricles.
4. Which electrode is considered the ‘ground’ electrode in a standard 12-lead EKG?
A. Left arm
B. Right leg
C. Left leg
D. Right arm
Answer: B
, Conceptual Explanation: The right leg (RL) electrode serves as the ground to reduce
electrical interference or AC artifact.
5. Using the 1500 method, calculate the heart rate if there are 20 small boxes between two R
waves.
A. 60 bpm
B. 100 bpm
C. 75 bpm
D. 150 bpm
Answer: C
Conceptual Explanation: 1500 divided by the number of small boxes (20) equals 75 beats
per minute.
6. An EKG shows an irregularly irregular rhythm with no discernible P waves. This most likely
indicates:
A. Atrial flutter
B. Ventricular tachycardia
C. Junctional rhythm
D. Atrial fibrillation
Answer: D
PRACTICE EXAM QUESTIONS AND
ANSWERS
1. Where is the electrode for lead V4 placed?
A. Fourth intercostal space, right sternal border
B. Fifth intercostal space, left anterior axillary line
C. Fifth intercostal space, left midclavicular line
D. Fourth intercostal space, left sternal border
Answer: C
Conceptual Explanation: Lead V4 is placed at the 5th intercostal space at the left
midclavicular line. A is V1, D is V2, and C is V5.
2. What is the standard gain setting for an EKG machine?
A. 5 mm/mV
B. 25 mm/mV
C. 20 mm/mV
D. 10 mm/mV
,Answer: D
Conceptual Explanation: The standard gain or sensitivity setting for an EKG is 10
mm/mV. 25 mm/sec is the standard paper speed.
3. A technician notes a rhythm with a PR interval of 0.24 seconds. Which of the following is
the most likely diagnosis?
A. Third-degree heart block
B. Second-degree Type I block
C. First-degree AV block
D. Normal sinus rhythm
Answer: C
Conceptual Explanation: A PR interval greater than 0.20 seconds indicates a first-degree
AV block, representing a delay in conduction from the atria to the ventricles.
4. Which electrode is considered the ‘ground’ electrode in a standard 12-lead EKG?
A. Left arm
B. Right leg
C. Left leg
D. Right arm
Answer: B
, Conceptual Explanation: The right leg (RL) electrode serves as the ground to reduce
electrical interference or AC artifact.
5. Using the 1500 method, calculate the heart rate if there are 20 small boxes between two R
waves.
A. 60 bpm
B. 100 bpm
C. 75 bpm
D. 150 bpm
Answer: C
Conceptual Explanation: 1500 divided by the number of small boxes (20) equals 75 beats
per minute.
6. An EKG shows an irregularly irregular rhythm with no discernible P waves. This most likely
indicates:
A. Atrial flutter
B. Ventricular tachycardia
C. Junctional rhythm
D. Atrial fibrillation
Answer: D
