Physics307L:People/Carrillo/Millikan Oil Drop

Millikan Oil Drop Lab Summary

• Please note that Ginny was my lab partner for this lab.

Brief Overview

The purpose of this lab was to measure the charge of an electron and compare our results to the accepted value of the electron. The procedure we followed can be found in in the PASCO Manual.

Our Data Results

• Calculated Charges

• [math]\displaystyle{ e_{1} = 1.0897 \cdot 10^{-20} +/- 3.6766 \cdot 10^{-20} }[/math]C
• [math]\displaystyle{ e_{2} = 6.2910 \cdot 10^{-21} +/- 3.7180 \cdot 10^{-21} }[/math]C
• [math]\displaystyle{ e_{3} = 4.8342 \cdot 10^{-20} +/- 6.9860 \cdot 10^{-21} }[/math]C
• [math]\displaystyle{ e_{3,Ionized} 7.0758 \cdot 10^{-20} +/- 1.0487 \cdot 10^{-20} }[/math]C
• [math]\displaystyle{ e_{4} = 2.0642 \cdot 10^{-17} +/- 3.0899 \cdot 10^{-18} }[/math]C
• [math]\displaystyle{ e_{4,Ionized} = 4.1899 \cdot 10^{-17} +/- 2.8041 \cdot 10^{-18} }[/math]C
• [math]\displaystyle{ e_{5} = 4.6468 \cdot 10^{-17} +/- 1.1432 \cdot 10^{-17} }[/math]C
• [math]\displaystyle{ e_{6} = 4.6110 \cdot 10^{-17} +/- 1.2955 \cdot 10^{-17} }[/math]C

The accepted value of the charge of an electron according to wikipedia is...

• [math]\displaystyle{ e=1.602176487(40)*10^-19C \,\! }[/math].

Error

• Please see my lab notebook on the Millikan Oil Drop for descriptions on why we had an error.

Conclusion

In conlusion, I thought this lab was really interesting. I am glad that I went through my calculations again and found my mistakes with my calculations because as you can see, our results were not as far off from the accepted value than the previous calculations. A few ways to make better measurements would be to measure the fall time and rise times over a larger distance and also have one person look throught the microscope and also do the timing because there would be better reflexes with stopping the time.