(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

This is for a lab class, I'm writing a report and giving a presentation. Tomorrow is the day and I've just received the final remarks on my lab writeup, most of which are simple and obvious enough, but this one really bugs me: I think my teacher is wrong.

Rutherford's Equation for scattering alpha particles on the nucleus is:

[tex]N(\theta)=\frac {K} {sin^4 (\frac {\theta} {2}})[/tex]

we can't compare this function directly to our data since it goes about the 0-angle, which leads to infinite, so we log transform it (here, I've assumed natural logarithm, but have since tried log base 10 just to be sure)

[tex]\log N = log K - 4log(sin(\frac{\theta} {2}) )[/tex]

So I plot logN vs log(sin(theta/2)) to verify a slope of -4. I don't quite get 4 (I get -3.5 for gold and -4.4 for silver), and I don't get a straight line, and in the red ink responses, there's a lot of "no! not in radians! do it in degrees! so that you won't get the bending at the edges!".

3. The attempt at a solution

I don't agree with my professor. I think the sin of theta in degrees or radians should be the same. Perhaps I am misunderstanding him. I made the mistake of putting units of 'radians' on my plot of the logarithmic transform of Rutherford's equation. I realize now the plot should be unitless. I'm wondering if I confused him with this, or whether he's making a point I'm missing.

Thank you for your time.

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# Homework Help: Rutherford Data Analysis

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