June 28, 2016 Tuesday
Post attack day 6
In the following year of 1909, Geiger and Marsden published their second experiment.
It was titled:
"On a diffuse reflection of the alpha particles".
For this experiment, the duo devised a small conical glass tube AB containing radium and bismuth-214.
Its open end was sealed with mica (silicate minerals).
This was their alpha particle emitter.
Beneath this conical source of radium they placed a lead plate P (which blocks alpha particles).
Beneath this they placed the fluorescent screen S.
The tube was placed such that the alpha particles could not directly strike the screen (better understandable if you see the schematic diagram).
What do u think they noticed?
A few scintillations on the screen.
How and why?
Some alpha particles would ricochet off air molecules and circumvent the lead plate (this is original particle physics at its classiest!).
Then they placed metal foil (like gold, aluminum etc) at the side of the lead plate right angle to the fluorescent screen.
The alpha particles were pointed at the metal foil.
How did the scintillations change?
The scintillations on the screen increased.
When counted, the scintillations were more with metals such as gold with higher atomic mass than with say aluminium (lower atomic mass).
Never forget my fellow ape, chemistry always ran faster than physics.
Geiger and Marsden did all this in a darkened room counting the number of scintillations.
It was this tedious labour that was providing insights into the fundamental basis of nature.
Nature was giving hints about herself but she was still waiting for more ingenuous experiments before she would reveal her true nature.
We shall continue with these fascinating series of experiments which in our high school is brushed off with one small page or a few paragraphs.
Stay tuned to the voice of Pan narrans or login at http://panarrans.blogspot.in/
Good night mon ami and my fellow cousin ape.
Post attack day 6
In the following year of 1909, Geiger and Marsden published their second experiment.
It was titled:
"On a diffuse reflection of the alpha particles".
For this experiment, the duo devised a small conical glass tube AB containing radium and bismuth-214.
Its open end was sealed with mica (silicate minerals).
This was their alpha particle emitter.
Beneath this conical source of radium they placed a lead plate P (which blocks alpha particles).
Beneath this they placed the fluorescent screen S.
The tube was placed such that the alpha particles could not directly strike the screen (better understandable if you see the schematic diagram).
What do u think they noticed?
A few scintillations on the screen.
How and why?
Some alpha particles would ricochet off air molecules and circumvent the lead plate (this is original particle physics at its classiest!).
Then they placed metal foil (like gold, aluminum etc) at the side of the lead plate right angle to the fluorescent screen.
The alpha particles were pointed at the metal foil.
How did the scintillations change?
The scintillations on the screen increased.
When counted, the scintillations were more with metals such as gold with higher atomic mass than with say aluminium (lower atomic mass).
Never forget my fellow ape, chemistry always ran faster than physics.
Geiger and Marsden did all this in a darkened room counting the number of scintillations.
It was this tedious labour that was providing insights into the fundamental basis of nature.
Nature was giving hints about herself but she was still waiting for more ingenuous experiments before she would reveal her true nature.
We shall continue with these fascinating series of experiments which in our high school is brushed off with one small page or a few paragraphs.
Stay tuned to the voice of Pan narrans or login at http://panarrans.blogspot.in/
Good night mon ami and my fellow cousin ape.
No comments:
Post a Comment