HOAG ECG EXAM COMPLETE QUESTIONS AND 100%
VERIFIED ANSWERS LATEST VERSION 2026
Q1. What is the normal heart rate range on an ECG?
ANSWER 60-100 beats per minute
Q2. What does the P wave represent?
ANSWER Atrial depolarization
Q3. What does the QRS complex represent?
ANSWER Ventricular depolarization
Q4. What does the T wave represent?
ANSWER Ventricular repolarization
Q5. What is the normal PR interval duration?
ANSWER 0.12-0.20 seconds (120-200 milliseconds)
Q6. What is the normal QRS duration?
ANSWER 0.06-0.10 seconds (60-100 milliseconds)
Q7. What is the normal QT interval?
ANSWER Less than half the R-R interval; typically 0.36-0.44 seconds
Q8. How many small boxes equal 0.04 seconds on standard ECG paper?
ANSWER One small box equals 0.04 seconds
Q9. How many large boxes equal 0.20 seconds on standard ECG paper?
ANSWER One large box equals 0.20 seconds (5 small boxes)
Q10. What is the standard paper speed for ECG recording?
ANSWER 25 mm/second
Q11. Which leads are considered the limb leads?
ANSWER Leads I, II, III, aVR, aVL, aVF
Q12. Which leads are considered the precordial (chest) leads?
,ANSWER V1, V2, V3, V4, V5, V6
Q13. What does lead II primarily view?
ANSWER The inferior wall of the heart
Q14. What do leads V1-V2 primarily view?
ANSWER The septal wall of the heart
Q15. What do leads V3-V4 primarily view?
ANSWER The anterior wall of the heart
Q16. What do leads V5-V6 primarily view?
ANSWER The lateral wall of the heart
Q17. What do leads II, III, and aVF view?
ANSWER The inferior wall of the heart
Q18. What do leads I and aVL view?
ANSWER The lateral wall of the heart
Q19. How do you calculate heart rate using the 300 rule?
ANSWER Count the number of large boxes between two consecutive R waves
and divide 300 by that number
Q20. How do you calculate heart rate using the 1500 rule?
ANSWER Count the number of small boxes between two consecutive R waves
and divide 1500 by that number
Q21. What is the normal axis range on an ECG?
ANSWER -30° to +90°
Q22. What indicates left axis deviation?
ANSWER Axis between -30° and -90°
Q23. What indicates right axis deviation?
ANSWER Axis between +90° and +180°
Q24. What is the quick method to determine axis?
ANSWER Look at leads I and aVF: both positive = normal axis
Q25. What is the standard calibration of an ECG machine?
ANSWER 1 mV = 10 mm (2 large boxes)
Q26. What does the U wave represent?
ANSWER Repolarization of the Purkinje fibers or papillary muscles
, Q27. In which leads should the P wave normally be upright?
ANSWER Leads I, II, aVF, and V2-V6
Q28. In which lead is the P wave normally inverted?
ANSWER Lead aVR
Q29. What is the normal P wave duration?
ANSWER Less than 0.12 seconds (3 small boxes)
Q30. What is the normal P wave amplitude?
ANSWER Less than 2.5 mm in limb leads; less than 1.5 mm in precordial leads
Q31. What is the isoelectric line on an ECG?
ANSWER The baseline between ECG waves when there is no electrical activity
Q32. What is the J point on an ECG?
ANSWER The junction between the end of the QRS complex and the beginning
of the ST segment
Q33. What is the significance of the ST segment?
ANSWER Represents the period between ventricular depolarization and
repolarization
Q34. How many seconds does a 6-second strip represent at standard speed?
ANSWER 6 seconds (30 large boxes)
Q35. What is the normal QRS axis in degrees?
ANSWER -30° to +90°
Q36. Define bradycardia on an ECG.
ANSWER Heart rate less than 60 beats per minute
Q37. Define tachycardia on an ECG.
ANSWER Heart rate greater than 100 beats per minute
Q38. What does a flat line on an ECG indicate?
ANSWER Asystole (no electrical activity)
Q39. What is the relationship between ECG and cardiac contraction?
ANSWER ECG shows electrical activity that precedes mechanical contraction
Q40. What does standardization of the ECG ensure?
ANSWER Accurate measurement of amplitude (height) of waves
Q41. What are the components of the cardiac cycle on ECG?
VERIFIED ANSWERS LATEST VERSION 2026
Q1. What is the normal heart rate range on an ECG?
ANSWER 60-100 beats per minute
Q2. What does the P wave represent?
ANSWER Atrial depolarization
Q3. What does the QRS complex represent?
ANSWER Ventricular depolarization
Q4. What does the T wave represent?
ANSWER Ventricular repolarization
Q5. What is the normal PR interval duration?
ANSWER 0.12-0.20 seconds (120-200 milliseconds)
Q6. What is the normal QRS duration?
ANSWER 0.06-0.10 seconds (60-100 milliseconds)
Q7. What is the normal QT interval?
ANSWER Less than half the R-R interval; typically 0.36-0.44 seconds
Q8. How many small boxes equal 0.04 seconds on standard ECG paper?
ANSWER One small box equals 0.04 seconds
Q9. How many large boxes equal 0.20 seconds on standard ECG paper?
ANSWER One large box equals 0.20 seconds (5 small boxes)
Q10. What is the standard paper speed for ECG recording?
ANSWER 25 mm/second
Q11. Which leads are considered the limb leads?
ANSWER Leads I, II, III, aVR, aVL, aVF
Q12. Which leads are considered the precordial (chest) leads?
,ANSWER V1, V2, V3, V4, V5, V6
Q13. What does lead II primarily view?
ANSWER The inferior wall of the heart
Q14. What do leads V1-V2 primarily view?
ANSWER The septal wall of the heart
Q15. What do leads V3-V4 primarily view?
ANSWER The anterior wall of the heart
Q16. What do leads V5-V6 primarily view?
ANSWER The lateral wall of the heart
Q17. What do leads II, III, and aVF view?
ANSWER The inferior wall of the heart
Q18. What do leads I and aVL view?
ANSWER The lateral wall of the heart
Q19. How do you calculate heart rate using the 300 rule?
ANSWER Count the number of large boxes between two consecutive R waves
and divide 300 by that number
Q20. How do you calculate heart rate using the 1500 rule?
ANSWER Count the number of small boxes between two consecutive R waves
and divide 1500 by that number
Q21. What is the normal axis range on an ECG?
ANSWER -30° to +90°
Q22. What indicates left axis deviation?
ANSWER Axis between -30° and -90°
Q23. What indicates right axis deviation?
ANSWER Axis between +90° and +180°
Q24. What is the quick method to determine axis?
ANSWER Look at leads I and aVF: both positive = normal axis
Q25. What is the standard calibration of an ECG machine?
ANSWER 1 mV = 10 mm (2 large boxes)
Q26. What does the U wave represent?
ANSWER Repolarization of the Purkinje fibers or papillary muscles
, Q27. In which leads should the P wave normally be upright?
ANSWER Leads I, II, aVF, and V2-V6
Q28. In which lead is the P wave normally inverted?
ANSWER Lead aVR
Q29. What is the normal P wave duration?
ANSWER Less than 0.12 seconds (3 small boxes)
Q30. What is the normal P wave amplitude?
ANSWER Less than 2.5 mm in limb leads; less than 1.5 mm in precordial leads
Q31. What is the isoelectric line on an ECG?
ANSWER The baseline between ECG waves when there is no electrical activity
Q32. What is the J point on an ECG?
ANSWER The junction between the end of the QRS complex and the beginning
of the ST segment
Q33. What is the significance of the ST segment?
ANSWER Represents the period between ventricular depolarization and
repolarization
Q34. How many seconds does a 6-second strip represent at standard speed?
ANSWER 6 seconds (30 large boxes)
Q35. What is the normal QRS axis in degrees?
ANSWER -30° to +90°
Q36. Define bradycardia on an ECG.
ANSWER Heart rate less than 60 beats per minute
Q37. Define tachycardia on an ECG.
ANSWER Heart rate greater than 100 beats per minute
Q38. What does a flat line on an ECG indicate?
ANSWER Asystole (no electrical activity)
Q39. What is the relationship between ECG and cardiac contraction?
ANSWER ECG shows electrical activity that precedes mechanical contraction
Q40. What does standardization of the ECG ensure?
ANSWER Accurate measurement of amplitude (height) of waves
Q41. What are the components of the cardiac cycle on ECG?
