Interpulse interval is defined as:

• A. The energy delivered per second
• B. The duration of a single pulse
• C. The time between successive pulses
• D. The time between the end of one pulse and the start of the next pulse

Answer: (D)

Interpulse interval is the silent gap that separates pulses in a pulsed stimulus. It is defined as the time between the end of one pulse and the start of the next. This precise end-to-start measure keeps the timing consistent regardless of how long each pulse lasts, which is why it’s the best description. The energy delivered per second describes power over time, not the spacing between pulses, and the duration of a single pulse refers to how long that pulse lasts. Even though “time between successive pulses” might seem similar, defining the interval as end-to-start avoids ambiguity when pulse durations vary.