What describes a spectrum that is not continuous?

• A. Power spectrum
• B. Line spectrum
• C. Intensive spectrum
• D. Acoustic spectrum

Answer: (B)

A line spectrum effectively describes a spectrum that is not continuous because it consists of distinct lines rather than a smooth curve. In this type of spectrum, energy is concentrated at specific frequencies, indicating that only certain frequencies are present at measurable levels. Consequently, gaps exist between these frequencies, which is what distinguishes a line spectrum from a continuous spectrum, where all frequencies over a range are represented without interruption.

These discrete lines result from specific energy transitions within a system, such as atoms transitioning between quantized energy levels. In contrast, a power spectrum and an acoustic spectrum often display continuous characteristics by representing how power is distributed across a range of frequencies, presenting a more fluid representation of the frequency content. The term "intensive spectrum" is not conventionally used in speech science in the context of describing a non-continuous spectrum, further supporting the uniqueness of the line spectrum as the correct choice.