# Physics307L F09:People/Mondragon/Notebook/070919

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## Excel File

Here is the Excel File that Lorenzo uploaded.

## Mass of the Electron(second week)

##this script is here to document the steps I took in processing data from the e/m ratio experiment. Hoorah. #octave #runs best in octave, then matlab varyAleft=[200,200,200,200 #ring radius on the left, varying current 1,1.2,1.4,1.6 #first row is voltage, second is current 4.9,4.8,4.6,4.5 #third is radius, and fourt is error on radius 0.2,0.2,0.3,0.3] #units are volts, amperes, centimeters, cm varyAright=[200,200,200,200 #ring radius on the right, varying current 1,1.2,1.4,1.6 4.3,3.7,3.2,3.1 0.1,0.2,0.1,0.2] varyVright=[200,220,240,260 #ring radius on the right, varying voltage 1,1,1,1 4.3,4.5,4.7,4.8 0.2,0.1,0.2,0.1] varyVleft=[200,220,240,260 #ring radius on the left, varying voltage 1,1,1,1 4.8,4.9,5.1,5.2 0.2,0.1,0.2,0.3] #the voltage and current uncertainties were constant, so, just assign constants for their error Verror=1 Aerror=0.01 #Clump all the data in one variable for convienence purposes rawData=[varyAleft varyAright varyVleft varyVright] #compute the bfield strength according to the current Bmagnitude=7.8e-4*rawData(2,:) BmagnitudeError=Aerror*7.8e-4 #propagate error via chain rule #e/m ratio computation. e/m= 2*voltage/(Bfield^2*radius(in meters)^2) e_mRatio=2*rawData(1,:)./(Bmagnitude.^2.*(rawData(3,:)*10^(-2)).^2) e_mError=2*Verror./(Bmagnitude.^2.*(rawData(3,:)*10^(-2)).^2+4*BmagnitudeError*rawData(1,:)./(Bmagnitude.^3.*(rawData(3,:)*10^(-2)).^2)+4*rawData(1,:).*rawData(4,:)*10^(-2)./(Bmagnitude.^2.*(rawData(3,:)*10^(-2)).^3)

--Tomas A. Mondragon 14:45, 10 October 2007 (CDT)