Relative electrical energy consumption for different light bulb color temperatures

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SUMMARY

The discussion centers on the relationship between light bulb color temperature and electrical energy consumption. It clarifies that while higher color temperatures emit light at shorter wavelengths, the energy consumption is determined by the bulb's power rating rather than the color temperature itself. Specifically, incandescent bulbs emit a small percentage of their electrical power as light, leading to no direct correlation between emitted light power and electrical power consumption. The correct understanding of intensity as power per area is crucial in this context.

PREREQUISITES
  • Understanding of light bulb technology, specifically incandescent bulbs
  • Knowledge of color temperature and its impact on light emission
  • Familiarity with the concept of intensity as power per area
  • Basic principles of electrical power consumption
NEXT STEPS
  • Research the differences in energy consumption between incandescent and LED bulbs
  • Learn about the physics of color temperature and its effect on light quality
  • Explore the relationship between power ratings and actual energy usage in various bulb types
  • Investigate the efficiency of different lighting technologies in terms of lumens per watt
USEFUL FOR

Electrical engineers, lighting designers, and consumers interested in energy-efficient lighting solutions will benefit from this discussion.

songoku
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Homework Statement
Please see below
Relevant Equations
maybe:

λmax . T = constant and E = hf
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I am not sure what the context of the question is. I am thinking this question is about light bulb emitting different colour at different temperature. The higher the temperature, the lower the wavelength hence the higher the energy emitted by the bulb so the energy consumption will also be higher.

My answer is (C) but correct answer is (B). What is my mistake?

Thanks
 
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The question says the intensity is the same for each colour. Do you know the definition of "intensity"?
 
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mjc123 said:
The question says the intensity is the same for each colour. Do you know the definition of "intensity"?
Intensity is power / area, so it means the power is the same and the energy consumption will be the same.

Thank you very much mjc123
 
The energy consumption is given by the power rating of the bulb. If it's an incandescent bulb, the power of the light emitted is just a small percentage of the electrical power. And there is no simple correlation between the two powers as a function of filament temperature. They may be emitting same power of light but this does not mean they use the same electrical power.
 
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