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

AI Thread Summary
The discussion revolves around how to linearize a logarithmic curve derived from the relationship between power radiated by a light bulb filament and its absolute temperature. The user has plotted the data and observed a natural logarithmic pattern but is unsure how to proceed with assuming a power function. It is clarified that by taking the natural logarithm of both power and temperature, one can plot ln(P) against ln(T) to obtain a linear relationship, where the slope represents the exponent in the power function. The conversation emphasizes that even with imperfect data, the slope of the trend line can provide the best estimate for the exponent. This approach aligns with the professor's expectations for the assignment.
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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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