Relative Intensity of Various Light Sources - Lab Experiment

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SUMMARY

The discussion centers on the confusion regarding the units of relative intensity in a lab experiment, specifically noted as w/m/s. Participants clarify that this notation likely contains a typographical error and should be expressed as Ws/m, indicating energy per unit area rather than power divided by velocity. The term "relative intensity" is deemed ambiguous, with suggestions that it may refer to a dimensionless ratio of total power or perceived brightness rather than a physical quantity. The conversation emphasizes the need for clear definitions in scientific contexts to avoid misinterpretation.

PREREQUISITES
  • Understanding of basic physics concepts, particularly light and intensity.
  • Familiarity with units of measurement in physics, especially watts (W) and steradians (sr).
  • Knowledge of the equation c = λv, relating the speed of light to wavelength and frequency.
  • Experience with data analysis in laboratory settings.
NEXT STEPS
  • Research the correct interpretation of relative intensity in optical physics.
  • Learn about the proper use of units in scientific measurements, focusing on energy and power.
  • Explore the concept of perceived brightness and its relation to light intensity.
  • Review common typographical errors in scientific notation and their implications.
USEFUL FOR

Students in physics or engineering disciplines, educators teaching optics, and researchers analyzing light intensity measurements will benefit from this discussion.

K_Physics
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Homework Statement


I've linked my data table down below. My problem is the relative intensity column. From the table, the units of relative intensity are w/m/s. I'm assuming this is power/velocity, where velocity is the speed of light. However, nowhere in the lab manual did it mention the power. So I was wondering whether there is a way to determine power, or perhaps an alternative approach. I'm fairly certain I did not miss any data collection steps. So any guidance here would be greatly appreciated.

Homework Equations


c = λv

The Attempt at a Solution


Relative Intensity = Power/Velocity?
 

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K_Physics said:

Homework Statement


I've linked my data table down below. My problem is the relative intensity column. From the table, the units of relative intensity are w/m/s. I'm assuming this is power/velocity, where velocity is the speed of light. However, nowhere in the lab manual did it mention the power. So I was wondering whether there is a way to determine power, or perhaps an alternative approach. I'm fairly certain I did not miss any data collection steps. So any guidance here would be greatly appreciated.

Homework Equations


c = λv

The Attempt at a Solution


Relative Intensity = Power/Velocity?
Power / velocity makes no sense in this context. W/m/s looks like a typo. If they really meant that it should be written Ws/m.
Relative intensity is not a well-defined term. The obvious interpretation would make it simply a ratio, such as a fraction of the total power. In that case it would be dimensionless.
If the context is perception, it might mean perceived brightness.
In some contexts the s could be a reference to steradians rather than seconds, but the W/m/s formula still makes no sense.
 
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