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HNQ
2:02 AM
1
Q: Physics of the convection oven

Ambrose SwaseyI don't understand how convection ovens can cook food faster than radiant heat ovens. Guides to convection ovens claim that they cook food 25-30% faster than radiant heat ovens, but do not really explain the physics of it. For example, let's say we have a big turkey. Now, we surround the turkey w...

 
 
6 hours later…
HNQ
8:24 AM
1
Q: Can a Helium balloon fly to the moon?

Ilya GazmanThe JP Aerospace's Tandem airship achieved a record-breaking 28,982 meters for the highest airship flight. Will it be possible to continue moving up to the moon by using the helium gas inside the balloon as a propeller? Assume the perfect conditions for the flight and that you have excellent cont...

 
 
1 hour later…
HNQ
9:40 AM
2
Q: EMF being equal through KVL

madness In the given figure,we connect three cells of different emf which are $V_1,V_2,V_3$ with a resistance $R$ in the first loop. Now suppose we emit current $I$ from $V_1$. $I$ gets divided into $I_1$ and $I_2$ with $I_1$ flowing through $V_2$ and $I_2$ through $V_3$. Now if i apply KVL in the secon...

 
 
6 hours later…
HNQ
4:00 PM
1
Q: Why were sparks created in Rutherford's alpha particle scattering experiment?

Roselynn SprinklesSo I just read that when alpha particle hit the gold foil sparks were created. And these flashes were used to determine the angle of scattering. So were the sparks created because the alpha particles (positive) excited the electrons in the gold foil? And is a spark just that? Light emitted due to...

 
 
1 hour later…
HNQ
5:16 PM
1
Q: How does s subshell not have a node in the center despite the nucleus being there?

NirabhraIn most images of 1s subshell I see that there's no node shown at the center, and even the formula n-l-1 gives 0 as the answer. But, isn't the nucleus experimentally proven to be at the center? And as the mass should be much more than individual electrons, I'm assuming the nucleus doesn't have la...

 
 
4 hours later…
HNQ
9:30 PM
3
Q: Where does all the energy in black holes go?

Sport6000The temperature inside of a black hole is almost absolute zero, so particles inside a black hole have almost zero motion. So if they don't give out any heat or light, where does all the energy it holds go? Edit: From an external reference frame, motion inside a black hole all but stops. (Carlo ...

 
 
2 hours later…
HNQ
11:37 PM
1
Q: What does it exactly mean by right and left functional derivatives?

KeithIn BV formalism of the gauge theory, we need to compute the right / left functional derivatives of the actions that include fermions. I do not quite see what it means by that. For example, let us think of the QCD action given as \begin{equation} S[\psi, \overline{\psi}]:= \int d^4x \text{ } \over...

 

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