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3 hours later…
6:58 AM
hey guys
 
@Luyw hi
 
why is it that when both transistor's junctions are forward biased the electrons doesn't just flow towards the base
and collide
NPN transistor
 
@Luyw which class do you study?
 
don't electrons travel from the lowest potential to highest?
1st year uni
first course on transistors ever
 
@Luyw first, look at a transistor circuit
base is connected to a ground,right?
in common base configuration
 
7:03 AM
well i am just seeing the representation of the junctions nto in a circuit
you know, rectangle with 3 parts
no circuit
jsut considering that Vb>Ve and Vb>Vc
"supposing"
 
@Luyw can you give me the picture you just saw?
 
but yeah I suppose if we make a circuit we'd have somethign liek this
 
@Luyw okay,common emitter configuration
 
THIS IS IT
this is it*
the other one is mine
 
@Luyw oh transistor working as switch
 
7:12 AM
consider my question again, why wouldn't all the electrons travel to the base?
surely Vb>Vc
so they are attracted to the highest potential
same Vb>Ve
 
@Luyw I will answer you question later after referring some of my books
 
Thank you!
 
well however my books does not talks about the movement of electrons when it works as a switch
 
x)
 
but let me try
 
7:17 AM
things dependent on others are full of uncertainties.
I hate this kind of uncertainties. I wish I can determine things on my own.
you can't understand this kind of frustration before you really experience it. You consider you can determine everything on your own but actually there remain people adapting to your needs automatically.
 
7:37 AM
@nihaljp are you trying to get yourself suspended?
 
 
2 hours later…
9:55 AM
-2
Q: I did ask the exact same question. But, why did Qmechanic put mine on hold, while he/she kindly edited the exact same earlier question?

Youngsub YoonIs it possible that gravitons don't exist, but are actually something like phonons? Of course, it is my fault that I didn't search first, but stackexchange search tab is not that visible.

 
 
6 hours later…
3:45 PM
Hey @JohnRennie Are you there for 3-4 minutes?
 
@Abcd hi, yes.
 
@JohnRennie Why does size of peaks keep increasing in $4\pi r^2 R^2$ curve but decrease in $R^2$ curve of orbital??
 
The radial function $R(r)$ overall decreases with distance in a roughly exponential fashion while $r^2$ increases with distance. So the product of $r^2$ and $R^2$ first increases then decreases again.
 
@JohnRennie I didn't understand increase/decrease part. Can you explain with an example??
 
I'm not sure there is too much significance to the exact ratios of the peak heights.
Well if we write $f(r) = r^2$ then $f(r)$ increases with increasing $r$.
 
3:53 PM
ya..
 
If we write $g(r) = e^{-r/a}$ (i.e. a hydrogen $1s$ orbital) then $g(r)$ decreases with increasing $r$.
If you take the product $h(r) = f(r) g(r)$ then $h(r)$ starts at zero for $r=0$, first increases with increasing $r$, then peaks, then decreases again at large $r$.
 
@JohnRennie See the two time stamps pls^^^
 
I've looked but I'm not sure what you are asking.
 
@JohnRennie In second case size of curve increases everytime after touching x axis while opposite happens in 1st case.
 
I'm not sure whether there's any great significance to that.
It's certainly interesting now you mention it.
There might be something in the mathematics of the solutions to the Schrodinger equation that means the peak values of $r^2\psi^2$ always increase with distance from the nucleus or it might be just a coincidence. I must confess I'm not sure which it is.
 
4:08 PM
Okay thanks!
 
 
2 hours later…
5:58 PM
@ZeroTheHero Sundays, amirite?
 
6:29 PM
Come on New Scientist. I know you have to sell magazines but that's no excuse for careless and misleading statements.
4
 
Why go all the trouble to reparametrise the curves, this paper is not yet comprehensible to me yet
 
@EmilioPisanty it's been a difficult week yes.
 
@ZeroTheHero it's the Easter holidays
at least, in Catholic-dominated countries it is
I gather you don't have that joy?
 
6:44 PM
@EmilioPisanty It's good the uni is closed tomorrow. I need to get my mind off a bad week and I suppose posting wasn't such a great idea. Thanks for being vigilant on my behalf.
 
@ZeroTheHero =)
no worries
it's particularly pleasant to have users that one just knows is going to react correctly, politely and swiftly when issues are pointed out
kudos to you, Zero =)
I'll delete my half of that thread shortly, there's no sense in keeping it around.
 
@EmilioPisanty it's particularly pleasant to have users that are knowledgeable enough to point out correctly, politely and swiftly issues with a post when they are arise.
 
@ZeroTheHero touché =)
=P
 

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