Final answer:
The wavelength of energy given off by warm objects is primarily in the infrared range of the electromagnetic spectrum. Infrared radiation is not visible but can be felt as heat, and is emitted by objects like a burner on a low setting. At higher temperatures, objects emit light in the visible spectrum.
Step-by-step explanation:
The wavelength of energy given off by warm objects is primarily in the infrared part of the electromagnetic spectrum. When objects are heated, they emit energy in various forms of electromagnetic radiation. The warmer the object, the shorter the wavelength at which the maximum power is emitted, which usually means a shift from infrared towards the visible spectrum when temperatures increase substantially.
Warm objects such as a burner on a low setting emit energy in the form of infrared radiation. This radiation is not visible to the human eye but can be felt as heat. The term infrared comes from the Latin word 'infra' meaning 'below'; infrared waves have frequencies which are below the red end of the visible spectrum, hence emitting energy as heat rather than light at typical warm temperatures.
As a point of reference, other types of electromagnetic radiation include ultraviolet rays, which are harmful to living tissues, and X-rays, used in medical imaging such as in dentistry, which have much shorter wavelengths and higher energies compared to infrared radiation.