# Thomson Model of the Atom

ColdFusion85
I am to explain whether the Thomson model of the atom fails at large scattering angles or at small ones...I obviously don't want the answer, but just some hints as to how I would determine this. Thanks in advance.

I know that the Thomson model predicts that there should be less than 1 degree of deflection for the alpha particles as they pass through the foil, and the Rutherford scattering formula shows that the number of particles that get deflected with respect to their scattering angle decreases as the scattering angle increases...so I am inclined to think that the Thomson model fails for large scattering angles...but the Rutherford formula clearly shows that most particles do get deflected at smaller angles, albeit not 1 degree...so isn't this agreeing with Thomson anyway? I am confused, please help.

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ColdFusion85 said:
I am to explain whether the Thomson model of the atom fails at large scattering angles or at small ones...I obviously don't want the answer, but just some hints as to how I would determine this. Thanks in advance.

I know that the Thomson model predicts that there should be less than 1 degree of deflection for the alpha particles as they pass through the foil, and the Rutherford scattering formula shows that the number of particles that get deflected with respect to their scattering angle decreases as the scattering angle increases...so I am inclined to think that the Thomson model fails for large scattering angles...but the Rutherford formula clearly shows that most particles do get deflected at smaller angles, albeit not 1 degree...so isn't this agreeing with Thomson anyway? I am confused, please help.
I think the question is asking: what observed scattering angles does the Thomson model fail to predict?

AM

ColdFusion85

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ColdFusion85 said:
It is not that difficult. If the Thomson model predicts small scattering angles and experiment shows that some alpha particles are deflected at small scattering angles, then it doesn't fail at small scattering angles. What the Thomson model does not predict or explain is an alpha particle scattering at large angles. Thomson's model, then, fails to predict the large angle scattering that was actually observed by Rutherford.

AM

deepak.c
is anybody having details of
structure of atom
nuetrons
protons
electrons
thomas model of atom
rutherford model of atom
bohr model of atom
atoms molecules
valencies table