User:Emran M. Qassem/Notebook/Physics 307L/2010/11/01: Difference between revisions
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* Measure the inner diameter of the Outer ring using the caliper. | * Measure the inner diameter of the Outer ring using the caliper. | ||
* Adjust the voltage down by 200V and repeat. | * Adjust the voltage down by 200V and repeat. | ||
Measure the ring diameter by measuring from the | Measure the ring diameter by measuring from the inside edge, as it is unclear where the edge ends on the outside one. | ||
<br style="clear:both;"/> | <br style="clear:both;"/> | ||
==Data== | ==Data== |
Revision as of 14:22, 21 December 2010
Electron Diffraction | <html><img src="/images/9/94/Report.png" border="0" /></html> Main project page <html><img src="/images/c/c3/Resultset_previous.png" border="0" /></html>Previous entry<html> </html>Next entry<html><img src="/images/5/5c/Resultset_next.png" border="0" /></html> |
Electron DiffractionPurposeUse the De Broglie relation "wavelength = planks constant / momentum" to measure the inner lattice spacing of the crystalline structure of graphite by sending an electron beam through a thin layer of the material and analyzing the diffraction pattern that it produces on a phosphorus Bulb surface. Equipment
Safety
SetupGolds Lab manual explains how to setup. Basically do the following:
ProcedureYou will notice that there are two rings glowing green on the white surface of the bulb (see image).
Measure the ring diameter by measuring from the inside edge, as it is unclear where the edge ends on the outside one.
DataCalculationsWe plotted the Diameter of the inner and outer ring vs one over the square root of the voltage and found a linear relationship. We then calculated the two different lattice spacings "d" by using the slope of the plots and the equation:
The values that we obtained for d were:
and
This standard error is the average standard error (column SE in the Excel sheet) calculated by the SE divided by the slope, multiplied by the value we obtained for d. The range of values of d we obtained are:
and
The actual values of d are:
and
ErrorAcknowledgments/Citations |