Question

when do objects usually radiate heat​

Answer 1

Answer:

All material objects emit electromagnetic radiation; the distribution of photon energies and fluxes emitted depend primarily on the object's temperature. ... Because the amount of radiation, and its spectrum depends on the temperature, it is sometimes called thermal radiation, or heat radiation.

Answer 2

Answer:

This motion of the particles contributes to the temperature of the object, with objects of "ordinary" temperatures (less than 1000 Kelvin) emitting their radiant heat primarily in the infrared spectrum of light.

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