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Forum » SpaceEngine » Science and Astronomy Discussions » Science and Astronomy Questions
Science and Astronomy Questions
spacerDate: Thursday, 30.06.2016, 07:19 | Message # 586
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sad i am sucks at math but i will try anyway!




"we began as wanderers, and we are wanderers still"
-carl sagan

-space engine photographer


Edited by spacer - Thursday, 30.06.2016, 07:28
 
spacerDate: Thursday, 30.06.2016, 08:03 | Message # 587
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ok i probably wrong because i am sucks but the speed of the decay is
20582227 meter per seconds.
its because 8.78mev=8780000 electronvolts
the mass is 4 (alpha)

is that true? lol





"we began as wanderers, and we are wanderers still"
-carl sagan

-space engine photographer
 
WatsisnameDate: Thursday, 30.06.2016, 08:11 | Message # 588
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That is the correct velocity. smile




 
spacerDate: Thursday, 30.06.2016, 08:15 | Message # 589
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Watsisname, yay! ^_^
ok i gonna continue.
too bad i didnt understand how to use latex for that caculation to write here





"we began as wanderers, and we are wanderers still"
-carl sagan

-space engine photographer


Edited by spacer - Thursday, 30.06.2016, 08:16
 
spacerDate: Thursday, 30.06.2016, 08:21 | Message # 590
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ok so to caculate the nuclear size we need:
1.2x10^-15x(212)^1:3 (yeah its hard to write Exponentiation Here, i write it as ^)
so its:
1.2x10^-15x(5.9627)
its:
7.15524x10^-15 meters!

smile am i right?





"we began as wanderers, and we are wanderers still"
-carl sagan

-space engine photographer
 
WatsisnameDate: Thursday, 30.06.2016, 08:36 | Message # 591
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You're doing great! I used a slightly bigger value for the nucleon radius (1.3 instead of 1.2 femtometers), so our answers may differ by a few percent, but that's not a problem.

See if you can get to the final answer without sharing the rest of your work. smile





 
spacerDate: Thursday, 30.06.2016, 08:39 | Message # 592
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ok, i will pm you, you are the one that can i ask if i correct! ^_^
first i will go to eat. i need a break, my brain broke.
never learned chimestry like that. i just finished my first year





"we began as wanderers, and we are wanderers still"
-carl sagan

-space engine photographer


Edited by spacer - Thursday, 30.06.2016, 08:40
 
WatsisnameDate: Thursday, 30.06.2016, 09:01 | Message # 593
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Sounds good, spacer! Definitely don't problem-solve on an empty stomach. smile And hey, while this is one of their 'easier' challenge questions, it is still quite challenging! You're doing awesome on it so far and huge props for deciding to put your mind to it!




 
spacerDate: Thursday, 30.06.2016, 10:28 | Message # 594
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Watsisname, and i just solved it! if i can! you all can! its very good practice to your mind,
if you want we will post the answer after a while! happy :)
it was 3 hours of fun math, yeah its right...FUN and MATH together.
learned new stuff and was great because i really love science. and chimestry and physics its something i just start to learn and love.
dont surrender! its will be easy at the end! wink





"we began as wanderers, and we are wanderers still"
-carl sagan

-space engine photographer


Edited by spacer - Thursday, 30.06.2016, 10:31
 
WatsisnameDate: Thursday, 30.06.2016, 10:34 | Message # 595
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Spacer solved it! Very well done!

The solution for the probability that the particle tunnels out of the nucleus any time it reaches the edge of the "energy barrier" provided by the strong nuclear force is

This is a really small probability! However, the barrier is so small, and the particle is moving so fast, that it has a huge number of opportunities to tunnel out in a short period of time. So the Polonium-212 can decay very quickly even though the quantum tunneling is such a rare event.





 
spacerDate: Thursday, 30.06.2016, 10:41 | Message # 596
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the actually long number to the ones who interested is:





"we began as wanderers, and we are wanderers still"
-carl sagan

-space engine photographer


Edited by spacer - Thursday, 30.06.2016, 10:42
 
WatsisnameDate: Thursday, 30.06.2016, 11:02 | Message # 597
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Ehh, most of those digits are not significant. smile Actually, the precision of the answer is limited to only one significant figure, since the half-life was given as 0.3 microseconds.




 
midtskogenDate: Thursday, 30.06.2016, 13:30 | Message # 598
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Quote Watsisname ()
This is a really small probability!

That points to a really really small probability for, say, tungsten isotopes. Philosophically, one can wonder why nature then bothers to give it a probability at all.





NIL DIFFICILE VOLENTI
 
WatsisnameDate: Thursday, 30.06.2016, 13:55 | Message # 599
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Yes indeed. The tunneling probability is based on penetration of the potential energy barrier, where the potential energy is determined by combination of nuclear and electric forces. The nuclear force binds protons and neutrons together, but only within a very short range -- beyond that range the electric repulsion will serve to repel the charges away from one another. So the potential has a hill with similar width as the nucleus that must be crossed over for a particle in the nucleus to escape.

This energy hill is too large to cross over normally. By classical physics, it is impossible. Instead, nature cheats. It tunnels straight through. It does this through the uncertainty principle -- the particle has wave-like properties, including an inherent uncertainty in where it actually is. There's a tiny chance that it can find itself outside the barrier, and escape. The probability depends on the energy of the particle and shape of the barrier, which ultimately depends on several constants of nature (speed of light, Planck constant, electric constant).

It turns out the 'tuning' of these constants must be exceedingly fine in order for physics to work the way it does. The very structure and stability of matter depends on it. And if we like to get philosophical, a deep question is why should these constants be tuned in the way that they are? smile





 
midtskogenDate: Thursday, 30.06.2016, 14:58 | Message # 600
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What does it take to reach zero tunnelling probability?




NIL DIFFICILE VOLENTI
 
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