Firefighter Practice Exam 2026 - Free Firefighter Practice Questions and Study Guide

The statement about heat wave wavelengths that is correct is that the longest is infrared. Infrared radiation is part of the electromagnetic spectrum and is known for its long wavelength compared to other forms of radiation. It is typically associated with heat, as objects emitting heat, such as the sun and fireplaces, release infrared radiation.

In the electromagnetic spectrum, wavelengths increase from gamma rays and X-rays (which are much shorter) to ultraviolet, visible light, and then up to infrared. Following infrared, there are microwave and radio wavelengths, which are even longer. This systematic arrangement of wavelengths is important in understanding how different forms of radiation interact with the environment, especially in the context of heat transfer.

The other statements provided do not accurately describe heat wave wavelengths. Ultrascopic is not a commonly recognized term within the context of the electromagnetic spectrum, and ultrared and infraviolet are not standard classifications; the correct terms would be ultraviolet and infrared. Thus, understanding the position of infrared in the spectrum is crucial for comprehending the behavior of heat waves.