21.4 Review & Assignment 13
In this lesson you focused on the following questions:
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How is blackbody radiation illustrated graphically?
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What is the relationship between colour and temperature?
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What are a quantum and a photon?
In this lesson you learned that a blackbody refers to a hypothetical object that absorbs all of the electromagnetic radiation that falls on it. The absorbed energy causes the blackbody to heat up and become a perfect radiator, emitting energy back to the environment in the form of electromagnetic radiation. The intensity and wavelength (or frequency) of the emitted radiation can be used to construct a blackbody radiation curve. Such curves illustrate the emitted energy distribution in terms of wavelength (or frequency) versus intensity for a blackbody at various temperatures. The curves showed that as the temperature increased, the frequency and intensity of the emitted EMR also increased. Attempts to explain this using classical physics did not provide answers.
You also learned that the radiation curve can be explained by assuming that energy is emitted from hot objects in discrete bundles, or photons, each capable of transferring a minimum quanta of energy associated with its wavelength and frequency according to Planck's formula, E = hf . Applying the formula to the electromagnetic spectrum reveals the energy of the photons in all the general classifications of the spectrum.
You also learned that for physics in general, the idea of the quantum marked the end of classical physics and the beginning of quantum physics by showing that light could be considered a photon, a particle.
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Assignment 13 Word
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