Only the best-physics(unit analysis) question

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The discussion focuses on verifying the relationship between the radius of a fireball (R) and time (t) using unit analysis. The equation provided expresses R in terms of energy (E), density (ρ), and time, with a specific focus on the proportionality of R to t raised to the power of -y/x. Participants express confusion about the vague nature of the question and the process of plotting log(R) versus log(t) to determine the slope, which indicates the exponent in the relationship. The importance of using logarithmic scales for better data fitting and interpretation is emphasized, particularly in understanding the implications of the slope. Clarification on the correct approach to graphing and interpreting the results is sought.
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Only the best--physics(unit analysis) question

Homework Statement


Ok, this is under the unit analysis section:

-----------> We can express the radius of the fireball (resulting from a bomb) R in terms of t, ρ and E as R= const2x E^(1/x)t^(-y/x)ρ^(−z/x).
Verify the relationship between R and t (That is R is proportional to t^(–y/x)) by plotting log (R) vs log (t) using the information provided in the pictures.
Fit the data of log (R) vs log (t) with a straight line. What is the slope of the
fit? What does the slope mean? Can you see why we are plotting log (R) vs
log (t) instead of R vs t?

--Basically, the pictures show the fireballs of a bomb with the diameter(m) at certain times(ms):
6ms--80m
120ms--110m
53ms--180m


Homework Equations


- Is it me, or is the question too vague? I am trying to understand what it's asking and how I should answer.


The Attempt at a Solution



In the previous question, I have found z= 1 y= -2 and x= 5 for the values in the R=... equation.

However, I don't know what they mean by plotting the log and fitting the data. I have tried graphing log (x) and log (x^(2/5)) but it doens't seem correct.

Thank you in advance.
 
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The times correct, particularly the second time.

6ms--80m
120ms--110m
53ms--180m

Normally when one has a function y = exp (kt), one can plot with semi-log, and the slope is the constant k.

if one has R = A tn, then ln R = ln A + n ln t
 
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