NEIEP Mechanics Practice Exam

What type of waveform has unequal rise and fall times, with one being instantaneous?

1. Sine wave

2. Square wave

3. Triangle wave

4. Sawtooth wave

The correct answer is: Sawtooth wave

The correct answer is the sawtooth wave. A sawtooth wave is characterized by its distinct shape, which includes a rapid rise or fall in voltage (the "instantaneous" change) followed by a slower decline or rise. This creates the unequal rise and fall times that define its waveform. In the context of this question, the sawtooth wave's sharp transition occurs quickly while the return to the starting point takes longer, which is essential to distinguishing it from other waveforms. For example, a square wave features equal rise and fall times, creating a symmetrical pattern. A sine wave has a smooth, continuous oscillation without distinct vertical shifts, and a triangle wave has linear rise and fall times that are equal in duration, resulting in a symmetrical waveform. Thus, the unique properties of the sawtooth wave make it the correct choice when describing a waveform with unequal rise and fall times and an instantaneous change.