BASIC ARRHYTHMIA SENTARA TEST PREP 2026 | 200
PRACTICE QUESTIONS & DETAILED ANSWERS | GRADED A+ |
VERIFIED SOLUTIONS
Questions 1–50: ECG Basics & Sinus Rhythms
1. What does the P wave represent on an ECG?
A) Ventricular depolarization
B) Atrial depolarization
C) Ventricular repolarization
D) Atrial repolarization
Answer: B) Atrial depolarization – The P wave represents atrial depolarization (contraction). It reflects
the electrical impulse spreading through the atria from the SA node.
2. What does the QRS complex represent?
A) Atrial depolarization
B) Ventricular repolarization
C) Ventricular depolarization
D) Purkinje fiber repolarization
Answer: C) Ventricular depolarization – The QRS complex represents ventricular depolarization
(contraction). This is the largest waveform on the ECG.
3. What is the normal duration of the PR interval in an adult?
,A) 0.06–0.10 seconds
B) 0.12–0.20 seconds
C) 0.20–0.32 seconds
D) 0.32–0.44 seconds
Answer: B) 0.12–0.20 seconds – The normal PR interval length is 0.12–0.20 seconds. It represents the
time from the start of atrial depolarization to the start of ventricular depolarization.
4. What is the normal duration of the QRS complex in an adult?
A) 0.12–0.20 seconds
B) 0.06–0.12 seconds
C) 0.04–0.06 seconds
D) 0.20–0.32 seconds
Answer: B) 0.06–0.12 seconds – The normal QRS duration is 0.06–0.12 seconds. A QRS > 0.12 seconds
indicates a bundle branch block or ventricular origin.
5. What is the normal duration of the QT interval?
A) 0.12–0.20 seconds
B) 0.06–0.12 seconds
C) 0.32–0.44 seconds
D) 0.44–0.52 seconds
Answer: C) 0.32–0.44 seconds – The normal QT interval is 0.32–0.44 seconds. It represents ventricular
depolarization and repolarization.
,6. How long is each small square on standard ECG paper?
A) 0.02 seconds
B) 0.04 seconds
C) 0.20 seconds
D) 1.0 seconds
Answer: B) 0.04 seconds – Each small square on ECG paper represents 0.04 seconds. Five small squares
make one large square (0.20 seconds).
7. How long is each large square (5 small squares) on standard ECG paper?
A) 0.04 seconds
B) 0.12 seconds
C) 0.20 seconds
D) 1.0 second
Answer: C) 0.20 seconds – Each large square represents 0.20 seconds. Five large squares equal 1 second.
8. Five large boxes on ECG paper represents:
A) 0.20 seconds
B) 0.04 seconds
C) 1 second
D) 6 seconds
, Answer: C) 1 second – Five large boxes (each 0.20 seconds) equals 1 second. This is used for rate
calculation.
9. What is the normal heart rate for Normal Sinus Rhythm?
A) Less than 60 bpm
B) 60–100 bpm
C) 101–150 bpm
D) Greater than 150 bpm
Answer: B) 60–100 bpm – Normal Sinus Rhythm has a rate of 60–100 beats per minute.
10. What indicates that the electrical impulse is generated by the sinus node and follows the normal
conduction pathway through the atria?
A) Inverted P waves
B) Rounded upright P waves
C) Absent P waves
D) Peaked P waves
Answer: B) Rounded upright P waves – Rounded upright P waves indicate that the impulse originates
from the sinus node and follows the normal conduction pathway.
11. What is the characteristic rate for Sinus Bradycardia?
A) Less than 60 bpm
B) 60–100 bpm
PRACTICE QUESTIONS & DETAILED ANSWERS | GRADED A+ |
VERIFIED SOLUTIONS
Questions 1–50: ECG Basics & Sinus Rhythms
1. What does the P wave represent on an ECG?
A) Ventricular depolarization
B) Atrial depolarization
C) Ventricular repolarization
D) Atrial repolarization
Answer: B) Atrial depolarization – The P wave represents atrial depolarization (contraction). It reflects
the electrical impulse spreading through the atria from the SA node.
2. What does the QRS complex represent?
A) Atrial depolarization
B) Ventricular repolarization
C) Ventricular depolarization
D) Purkinje fiber repolarization
Answer: C) Ventricular depolarization – The QRS complex represents ventricular depolarization
(contraction). This is the largest waveform on the ECG.
3. What is the normal duration of the PR interval in an adult?
,A) 0.06–0.10 seconds
B) 0.12–0.20 seconds
C) 0.20–0.32 seconds
D) 0.32–0.44 seconds
Answer: B) 0.12–0.20 seconds – The normal PR interval length is 0.12–0.20 seconds. It represents the
time from the start of atrial depolarization to the start of ventricular depolarization.
4. What is the normal duration of the QRS complex in an adult?
A) 0.12–0.20 seconds
B) 0.06–0.12 seconds
C) 0.04–0.06 seconds
D) 0.20–0.32 seconds
Answer: B) 0.06–0.12 seconds – The normal QRS duration is 0.06–0.12 seconds. A QRS > 0.12 seconds
indicates a bundle branch block or ventricular origin.
5. What is the normal duration of the QT interval?
A) 0.12–0.20 seconds
B) 0.06–0.12 seconds
C) 0.32–0.44 seconds
D) 0.44–0.52 seconds
Answer: C) 0.32–0.44 seconds – The normal QT interval is 0.32–0.44 seconds. It represents ventricular
depolarization and repolarization.
,6. How long is each small square on standard ECG paper?
A) 0.02 seconds
B) 0.04 seconds
C) 0.20 seconds
D) 1.0 seconds
Answer: B) 0.04 seconds – Each small square on ECG paper represents 0.04 seconds. Five small squares
make one large square (0.20 seconds).
7. How long is each large square (5 small squares) on standard ECG paper?
A) 0.04 seconds
B) 0.12 seconds
C) 0.20 seconds
D) 1.0 second
Answer: C) 0.20 seconds – Each large square represents 0.20 seconds. Five large squares equal 1 second.
8. Five large boxes on ECG paper represents:
A) 0.20 seconds
B) 0.04 seconds
C) 1 second
D) 6 seconds
, Answer: C) 1 second – Five large boxes (each 0.20 seconds) equals 1 second. This is used for rate
calculation.
9. What is the normal heart rate for Normal Sinus Rhythm?
A) Less than 60 bpm
B) 60–100 bpm
C) 101–150 bpm
D) Greater than 150 bpm
Answer: B) 60–100 bpm – Normal Sinus Rhythm has a rate of 60–100 beats per minute.
10. What indicates that the electrical impulse is generated by the sinus node and follows the normal
conduction pathway through the atria?
A) Inverted P waves
B) Rounded upright P waves
C) Absent P waves
D) Peaked P waves
Answer: B) Rounded upright P waves – Rounded upright P waves indicate that the impulse originates
from the sinus node and follows the normal conduction pathway.
11. What is the characteristic rate for Sinus Bradycardia?
A) Less than 60 bpm
B) 60–100 bpm
