Relative electrical energy consumption for different light bulb color temperatures

Click For Summary

Homework Help Overview

The discussion revolves around the relative electrical energy consumption of different light bulbs based on their color temperatures. Participants are exploring the relationship between temperature, wavelength, and energy consumption in light bulbs.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants are questioning the definitions and implications of intensity in relation to energy consumption. There is an exploration of how power ratings and filament temperatures affect the electrical power used by different types of bulbs.

Discussion Status

The discussion is active, with participants providing insights into the definitions of intensity and the relationship between emitted light power and electrical power consumption. There is an acknowledgment of differing perspectives on how these factors interact.

Contextual Notes

Some participants are noting the assumption that intensity is the same across different colors, which may influence their understanding of energy consumption. There is also mention of the specific characteristics of incandescent bulbs in relation to their power ratings.

songoku
Messages
2,509
Reaction score
393
Homework Statement
Please see below
Relevant Equations
maybe:

λmax . T = constant and E = hf
1727268231822.png


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
 
Physics news on Phys.org
The question says the intensity is the same for each colour. Do you know the definition of "intensity"?
 
  • Like
Likes   Reactions: berkeman and songoku
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.
 
  • Like
Likes   Reactions: songoku

Similar threads

Replies
2
Views
1K
Replies
1
Views
1K
  • · Replies 6 ·
Replies
6
Views
3K
Replies
4
Views
2K
Replies
1
Views
3K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K