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What did researchers find about the intensity of radiation at different wavelengths?
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They found that the intensity of radiation varies with the wavelength and that maximum intensity occurs at a specific wavelength.
What concept did the photoelectric effect challenge?
The photoelectric effect challenged the wave nature of light, showing that light energy travels as particles.
What is a black body in the context of radiation?
A black body is an object that absorbs all incident radiations and emits radiation when heated.
What relationship is shown in the intensity vs wavelength graph of radiations emitted by heated objects?
The graph shows that there is a specific wavelength at which the maximum intensity of radiation occurs.
What does a black body do with incident radiations?
A black body absorbs all incident radiations.
Why does a perfect black object appear black?
Because it absorbs all incident light and does not reflect any light.
What demonstrates that light has a particle nature instead of a wave nature?
The Photoelectric Effect
What crucial contribution did Max Planck make to our understanding of light?
Max Planck's Quantum Theory explained the particle nature of light, showing that light consists of energy packets (quanta).
How did Max Planck's Quantum Theory provide evidence for the particle nature of light?
It explained that light energy is quantized and travels in discrete packets called quanta.
What occurs when an object is heated in terms of radiation?
The object emits electromagnetic radiation which can be observed as changing colors at different temperatures.
What happens to the colors of radiations emitted by a heated object as the temperature increases?
The colors change from red to orange to yellow to blue, indicating different wavelengths.
Why did the wave theory fail to explain the color change of heated objects?
The wave theory failed because it could not account for the varying energy packets at different wavelengths emitted by heated objects.
How does the wave theory of light explain the energy of electromagnetic radiation?
The wave theory states that the energy of electromagnetic radiation is proportional to its intensity and independent of frequency and wavelength.
Who proposed that light consists of particles called quanta?
Max Planck
What evidence supports the particle nature of light as per Hot Body Radiation?
The emission of different colors at different temperatures indicated that the radiation emitted consists of particles with specific energy levels.
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