BASIC ARRHYTHMIA SENTARA TEST – 200 MCQs WITH
CORRECT ANSWERS AND DETAILED RATIONALES| VERIFIED STUDY
GUIDE | LATEST UPDATE | GUARANTEED PASS
SECTION 1: ECG BASICS, MEASUREMENTS, AND CONDUCTION (Q1–Q30)
Q1. What does the P wave represent on an ECG?
A) Ventricular depolarization
B) Atrial depolarization
C) Ventricular repolarization
D) Atrial repolarization
Correct Answer: B
Rationale: The P wave is the first waveform and represents atrial depolarization,
which leads to atrial contraction.
Q2. What does the QRS complex represent?
A) Atrial depolarization
B) Ventricular repolarization
C) Ventricular depolarization
D) Purkinje repolarization
Correct Answer: C
Rationale: The QRS complex represents ventricular depolarization and is usually
the largest waveform.
Q3. What is the normal PR interval?
A) 0.06–0.10 sec
B) 0.12–0.20 sec
C) 0.20–0.32 sec
D) 0.32–0.44 sec
Correct Answer: B
Rationale: Normal PR interval is 0.12–0.20 seconds (3–5 small boxes), measuring
from start of P wave to start of QRS.
Q4. What is the normal QRS duration?
A) 0.12–0.20 sec
B) 0.06–0.12 sec
C) 0.04–0.06 sec
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,D) 0.20–0.32 sec
Correct Answer: B
Rationale: A normal QRS is 0.06–0.12 seconds. Wider QRS suggests ventricular
origin or bundle branch block.
Q5. What is the normal QT interval?
A) 0.12–0.20 sec
B) 0.06–0.12 sec
C) 0.32–0.44 sec
D) 0.44–0.52 sec
Correct Answer: C
Rationale: Normal QT is 0.32–0.44 seconds and varies with rate. It represents
ventricular depolarization and repolarization.
Q6. One small square on standard ECG paper equals:
A) 0.02 sec
B) 0.04 sec
C) 0.20 sec
D) 0.40 sec
Correct Answer: B
Rationale: At 25 mm/sec, each small square is 0.04 seconds.
Q7. One large box on standard ECG paper equals:
A) 0.04 sec
B) 0.10 sec
C) 0.20 sec
D) 0.40 sec
Correct Answer: C
Rationale: One large box contains five small boxes: 5 × 0.04 = 0.20 seconds.
Q8. Standard ECG paper speed is:
A) 10 mm/sec
B) 25 mm/sec
C) 50 mm/sec
D) 100 mm/sec
Correct Answer: B
Rationale: Standard speed is 25 mm/second, making time measurements
consistent.
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,Q9. Standard ECG calibration is:
A) 10 mm = 1 mV
B) 5 mm = 1 mV
C) 20 mm = 1 mV
D) 1 mm = 1 mV
Correct Answer: A
Rationale: A standard calibration mark is 10 mm high (two large boxes) and equals
1 mV.
Q10. The primary pacemaker of the heart is the:
A) AV node
B) SA node
C) Bundle of His
D) Purkinje fibers
Correct Answer: B
Rationale: The SA node has the fastest intrinsic rate and normally initiates the
impulse.
Q11. The intrinsic rate of the SA node is:
A) 20–40 bpm
B) 40–60 bpm
C) 60–100 bpm
D) 100–150 bpm
Correct Answer: C
Rationale: The SA node fires at 60–100 beats per minute.
Q12. The intrinsic rate of the AV junction is:
A) 60–100 bpm
B) 40–60 bpm
C) 20–40 bpm
D) 100–150 bpm
Correct Answer: B
Rationale: The AV junction acts as a backup pacemaker at 40–60 bpm.
Q13. The intrinsic rate of the ventricles/Purkinje fibers is:
A) 60–100 bpm
B) 40–60 bpm
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, C) 20–40 bpm
D) 100–120 bpm
Correct Answer: C
Rationale: Ventricular tissue fires at 20–40 bpm and is the last-resort pacemaker.
Q14. The T wave represents:
A) Atrial depolarization
B) Ventricular depolarization
C) Ventricular repolarization
D) Atrial repolarization
Correct Answer: C
Rationale: The T wave represents ventricular repolarization.
Q15. A prominent U wave is most associated with:
A) Hyperkalemia
B) Hypokalemia
C) Hypercalcemia
D) Digoxin toxicity
Correct Answer: B
Rationale: Prominent U waves are classically associated with hypokalemia.
Q16. The PR segment normally measures:
A) 0.12–0.20 sec
B) 0.04–0.08 sec
C) 0.20–0.32 sec
D) 0.32–0.44 sec
Correct Answer: B
Rationale: The PR segment is the flat line after the P wave and normally measures
0.04–0.08 seconds.
Q17. A delta wave is associated with:
A) Myocardial infarction
B) Wolff-Parkinson-White syndrome
C) Atrial fibrillation
D) Hyperkalemia
Correct Answer: B
Rationale: A delta wave is a slurred QRS upstroke caused by ventricular pre-
excitation in WPW.
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CORRECT ANSWERS AND DETAILED RATIONALES| VERIFIED STUDY
GUIDE | LATEST UPDATE | GUARANTEED PASS
SECTION 1: ECG BASICS, MEASUREMENTS, AND CONDUCTION (Q1–Q30)
Q1. What does the P wave represent on an ECG?
A) Ventricular depolarization
B) Atrial depolarization
C) Ventricular repolarization
D) Atrial repolarization
Correct Answer: B
Rationale: The P wave is the first waveform and represents atrial depolarization,
which leads to atrial contraction.
Q2. What does the QRS complex represent?
A) Atrial depolarization
B) Ventricular repolarization
C) Ventricular depolarization
D) Purkinje repolarization
Correct Answer: C
Rationale: The QRS complex represents ventricular depolarization and is usually
the largest waveform.
Q3. What is the normal PR interval?
A) 0.06–0.10 sec
B) 0.12–0.20 sec
C) 0.20–0.32 sec
D) 0.32–0.44 sec
Correct Answer: B
Rationale: Normal PR interval is 0.12–0.20 seconds (3–5 small boxes), measuring
from start of P wave to start of QRS.
Q4. What is the normal QRS duration?
A) 0.12–0.20 sec
B) 0.06–0.12 sec
C) 0.04–0.06 sec
1
,D) 0.20–0.32 sec
Correct Answer: B
Rationale: A normal QRS is 0.06–0.12 seconds. Wider QRS suggests ventricular
origin or bundle branch block.
Q5. What is the normal QT interval?
A) 0.12–0.20 sec
B) 0.06–0.12 sec
C) 0.32–0.44 sec
D) 0.44–0.52 sec
Correct Answer: C
Rationale: Normal QT is 0.32–0.44 seconds and varies with rate. It represents
ventricular depolarization and repolarization.
Q6. One small square on standard ECG paper equals:
A) 0.02 sec
B) 0.04 sec
C) 0.20 sec
D) 0.40 sec
Correct Answer: B
Rationale: At 25 mm/sec, each small square is 0.04 seconds.
Q7. One large box on standard ECG paper equals:
A) 0.04 sec
B) 0.10 sec
C) 0.20 sec
D) 0.40 sec
Correct Answer: C
Rationale: One large box contains five small boxes: 5 × 0.04 = 0.20 seconds.
Q8. Standard ECG paper speed is:
A) 10 mm/sec
B) 25 mm/sec
C) 50 mm/sec
D) 100 mm/sec
Correct Answer: B
Rationale: Standard speed is 25 mm/second, making time measurements
consistent.
2
,Q9. Standard ECG calibration is:
A) 10 mm = 1 mV
B) 5 mm = 1 mV
C) 20 mm = 1 mV
D) 1 mm = 1 mV
Correct Answer: A
Rationale: A standard calibration mark is 10 mm high (two large boxes) and equals
1 mV.
Q10. The primary pacemaker of the heart is the:
A) AV node
B) SA node
C) Bundle of His
D) Purkinje fibers
Correct Answer: B
Rationale: The SA node has the fastest intrinsic rate and normally initiates the
impulse.
Q11. The intrinsic rate of the SA node is:
A) 20–40 bpm
B) 40–60 bpm
C) 60–100 bpm
D) 100–150 bpm
Correct Answer: C
Rationale: The SA node fires at 60–100 beats per minute.
Q12. The intrinsic rate of the AV junction is:
A) 60–100 bpm
B) 40–60 bpm
C) 20–40 bpm
D) 100–150 bpm
Correct Answer: B
Rationale: The AV junction acts as a backup pacemaker at 40–60 bpm.
Q13. The intrinsic rate of the ventricles/Purkinje fibers is:
A) 60–100 bpm
B) 40–60 bpm
3
, C) 20–40 bpm
D) 100–120 bpm
Correct Answer: C
Rationale: Ventricular tissue fires at 20–40 bpm and is the last-resort pacemaker.
Q14. The T wave represents:
A) Atrial depolarization
B) Ventricular depolarization
C) Ventricular repolarization
D) Atrial repolarization
Correct Answer: C
Rationale: The T wave represents ventricular repolarization.
Q15. A prominent U wave is most associated with:
A) Hyperkalemia
B) Hypokalemia
C) Hypercalcemia
D) Digoxin toxicity
Correct Answer: B
Rationale: Prominent U waves are classically associated with hypokalemia.
Q16. The PR segment normally measures:
A) 0.12–0.20 sec
B) 0.04–0.08 sec
C) 0.20–0.32 sec
D) 0.32–0.44 sec
Correct Answer: B
Rationale: The PR segment is the flat line after the P wave and normally measures
0.04–0.08 seconds.
Q17. A delta wave is associated with:
A) Myocardial infarction
B) Wolff-Parkinson-White syndrome
C) Atrial fibrillation
D) Hyperkalemia
Correct Answer: B
Rationale: A delta wave is a slurred QRS upstroke caused by ventricular pre-
excitation in WPW.
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