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1d
comment Practical (maybe naive) question on boiling water
@Val you clearly haven't thought about this. Boiling is the majority of energy transport which is convection. There will be a slight temperature gradient with the bottom being slightly higher due to the marginally higher pressure. Put those two together and there is a greater chance that the water in the bottle will boil. The walls of the bottle shut down teh convective processes for inside the bottle.
2d
comment Stopping angular momentum to obtain a particular angle
You need to implement what is known as a PID controller (Proportional Integral Derivative) knowing what feedback signals you have would be nice.
2d
comment How would an X-ray scanner identify a mirror?
Unless of course they are back-scatter X-Ray machines.
2d
answered Mass of air inside air balloon
2d
comment Practical (maybe naive) question on boiling water
+1 Also the bottle shuts down the convection currents that also transport energy.
Jul
18
answered How does electrostatic force affect electronic devices?
Jul
18
awarded  Commentator
Jul
18
comment Why do we test electric fields with positive charges and not negative ones?
opposite and parallel is not the best pairing of words, perhaps opposite and towards or away from and towards ?
Jul
16
answered photo electric effect question
Jul
12
answered Why does a short circuit generate fire?
Jul
11
comment Flying eggshells
@AnotherUser Nope, there is at least 2 orders of magnitude separating the buoyancy force vs the shell weight.
Jul
10
awarded  Critic
Jul
8
answered Layer thickness measurement
Jul
7
answered Flying eggshells
Oct
12
comment Probability to create an electron - hole pair inside Si
@boyfarrell I did as you suggested, I would have thought the statement that " ... alpha is a strong function of wavelength" and the subsequent curve would have been a clue ... But if it helps I changed it. Thanks for the suggestion.
Oct
12
revised Probability to create an electron - hole pair inside Si
added 9 characters in body
Oct
11
awarded  Editor
Oct
11
revised Probability to create an electron - hole pair inside Si
added 497 characters in body
Oct
11
comment Probability to create an electron - hole pair inside Si
This is not wrong. Let me explain. The energy of the photon is the selected by the wavelength. The photon moving through the Si leaves a a probability trail of e/h pairs with a characteristic depth that \$ e^{-1} \$ absorption. That formulate above is a probability. To check this out look at "Donati, Silvano". "Photodetectors: Devices, Circuits and Applications". Prentice Hall PTR, 1999. The graph above is from internal data that I've collected and verified. Do a little research.
Oct
11
comment Probability to create an electron - hole pair inside Si
Oh boy ... I am assuming the external QE ** is one. i.e. every photon **once ** it is the Si is subject to the probability of absorption as defined above. Since no external conditions are noted one simply needs to apply this to the photons that **do make it into the Si.