The frequency of body heat, which is in the form of infrared radiation, is lower than the frequency of the visible light spectrum.
The visible light spectrum consists of electromagnetic waves with frequencies ranging from approximately 430 to 750 terahertz (THz), corresponding to wavelengths of 400 to 700 nanometers (nm). These frequencies are capable of stimulating the human eye's photoreceptor cells and are thus detectable as visible light.
On the other hand, infrared radiation, including the thermal radiation emitted by the human body, has lower frequencies than visible light. Infrared radiation ranges from about 300 GHz to 430 THz, with corresponding wavelengths between 1 millimeter and 750 nanometers. Infrared radiation is not visible to the human eye but can be detected by certain devices, such as thermal cameras or infrared sensors.
In summary, body heat, which is emitted as infrared radiation, has a lower frequency compared to the visible light spectrum.