![]() ![]() Your body, when at its normal temperature of about 300 K, radiates most strongly in the infrared part of the spectrum. For example, the Sun, whose surface temperature is in the range between 5000 K and 6000 K, radiates most strongly in a range of wavelengths about 560 nm in the visible part of the electromagnetic spectrum. The temperature ( T) of the object that emits radiation, or the emitter, determines the wavelength at which the radiated energy is at its maximum. This is the underlying principle of the incandescent light bulb: A hot metal filament glows red, and when heating continues, its glow eventually covers the entire visible portion of the electromagnetic spectrum. ![]() As its temperature rises, the body glows with the colors corresponding to ever-smaller wavelengths of the electromagnetic spectrum. ![]() We also know by observation that when a body is heated and its temperature rises, the perceived wavelength of its emitted radiation changes from infrared to red, and then from red to orange, and so forth. In an earlier chapter, we learned that a cooler body radiates less energy than a warmer body. Explain Planck’s hypothesis of energy quantaĪll bodies emit electromagnetic radiation over a range of wavelengths.Apply Wien’s and Stefan’s laws to analyze radiation emitted by a blackbody.By the end of this section, you will be able to: ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |