July 03, 2016 Sunday
Using this apparatus, Geiger and Marsden found that the number of alpha particles that are deflected by the given angle phi is indeed proportional to:
csc^4phi/2 (as in Rutherford mathematical model).
Secondly they tested for the scattering with varying thickness (t) of gold foil.
They found that the number of scintillations on the screen was indeed proportional to the thickness as long as the thickness was small.
Thirdly, they sought to study the scattering pattern with relation to the square of the nuclear charge Qn^2 (still unaware whether the charge was positive or negative).
For this they used the foils of gold, silver, copper and aluminum.
They divided the number of scintillations per minute by the respective foil's air equivalent (bit technical I guess).
This they divided yet again by the square root of the atomic weight (foils of equal stopping power have the number of atoms per unit area proportional to the square root of the atomic weight).
The data once again showed that the scattering s was proportional to the square of the nuclear charge Qn^2.
Finally, they tested how the scattering (s) varied with the speed of the alpha particles.
They slowed the alpha particles by placing sheets of mica in front of the radon (R).
Once again, within the range of experimental error, the number of scintillations was indeed proportional to inverse fourth power of the velocity 1/v^4.
Geiger and Marsden published these results in 1913 in a paper titled:
"The Laws of Deflexion of alpha particles through Large Angles".
It is quite remarkable how humble the titles are to such ground breaking papers (remember the 1965 paper by Penzias and Wilson:
"A Measurement of Excess Antenna Temperature at 4080 Mc/s".)
We will continue with this story further.
Stay tuned to the voice of an average storytelling chimpanzee or login at http://panarrans.blogspot.in/
Good night mon ami and my fellow cousin ape.
Using this apparatus, Geiger and Marsden found that the number of alpha particles that are deflected by the given angle phi is indeed proportional to:
csc^4phi/2 (as in Rutherford mathematical model).
Secondly they tested for the scattering with varying thickness (t) of gold foil.
They found that the number of scintillations on the screen was indeed proportional to the thickness as long as the thickness was small.
Thirdly, they sought to study the scattering pattern with relation to the square of the nuclear charge Qn^2 (still unaware whether the charge was positive or negative).
For this they used the foils of gold, silver, copper and aluminum.
They divided the number of scintillations per minute by the respective foil's air equivalent (bit technical I guess).
This they divided yet again by the square root of the atomic weight (foils of equal stopping power have the number of atoms per unit area proportional to the square root of the atomic weight).
The data once again showed that the scattering s was proportional to the square of the nuclear charge Qn^2.
Finally, they tested how the scattering (s) varied with the speed of the alpha particles.
They slowed the alpha particles by placing sheets of mica in front of the radon (R).
Once again, within the range of experimental error, the number of scintillations was indeed proportional to inverse fourth power of the velocity 1/v^4.
Geiger and Marsden published these results in 1913 in a paper titled:
"The Laws of Deflexion of alpha particles through Large Angles".
It is quite remarkable how humble the titles are to such ground breaking papers (remember the 1965 paper by Penzias and Wilson:
"A Measurement of Excess Antenna Temperature at 4080 Mc/s".)
We will continue with this story further.
Stay tuned to the voice of an average storytelling chimpanzee or login at http://panarrans.blogspot.in/
Good night mon ami and my fellow cousin ape.
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