Lab Exercise: How do I make a logarithmic curve linear?

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SUMMARY

The discussion centers on transforming a logarithmic curve into a linear format by analyzing the relationship between power (P) radiated by a light bulb filament and its absolute temperature (T). The user successfully plotted the data and recognized that applying a logarithmic transformation could yield a linear relationship. By using the equation ln(P) = n*ln(T), the user can determine the slope (n) from the trend line of the ln(P) vs. ln(T) graph, which is essential for modeling the power function accurately.

PREREQUISITES
  • Understanding of logarithmic functions and their properties
  • Familiarity with linear regression analysis
  • Basic knowledge of power functions and their mathematical representation
  • Experience with data plotting tools (e.g., Python's Matplotlib or Excel)
NEXT STEPS
  • Learn how to perform linear regression on transformed data using Python's SciPy library
  • Explore the concept of power functions in depth, focusing on the relationship between variables
  • Study the method of least squares for fitting curves to data
  • Investigate the implications of data imperfections on slope calculations in logarithmic transformations
USEFUL FOR

Students in physics or engineering, data analysts, and anyone involved in experimental data analysis seeking to understand the transformation of nonlinear relationships into linear formats.

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Homework Statement


In a certain experiment, the power (P) radiated by a light bulb filament was measured as a function of the filament's absolute temperature (T).

Data:
P(W)
0.45
0.95
1.8
3.5
5.6

T(K)
1000
1200
1500
1800
2000

(a) Plot the data (Done)

(b) Assume a power function and re-plot the data.

Homework Equations



Unsure.

The Attempt at a Solution



I plotted the data and it looks like a natural logarithm. I'm not sure what to do next. Raising each T value to the power of 2 straightens out the curve a bit but not completely. Is that what it means to assume a power function? If a power function is y=kx^a, how do I know which exact a to take and where do I get k from? Thanks.
 
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Suppose P = T^n.
Then ln(P) = ln(T^n) = n*ln(T).
If you graph your data as ln(P) vs ln(T), (and the data is perfect) you will get a straight line with slope n. Imperfect data (isn't it always?), the slope of a trend line is the best value for n.
 
Thank you. That was what my professor was looking for.
 

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