Question

In an ECG of a normal healthy person, the duration of the R-R interval is about:

• A. 0.12 sec
• B. 0.08 sec
• C. 0.8 sec
• D. 0.4 sec

Hint:

The R-R interval in an ECG represents one full cardiac cycle and can be used to calculate heart rate.

Answer 1

The Correct Option is C

Step 1: Understanding the R-R Interval in ECG 
- The R-R interval represents one complete cardiac cycle.
- It is used to determine heart rate. 

Step 2: Calculating the Interval 
- The normal resting heart rate is 60-100 beats per minute.
- The R-R interval is approximately 0.8 seconds for a heart rate of 75 bpm. 

Step 3: Conclusion 
Since the R-R interval is about 0.8 seconds, the correct answer is Option (3).