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HNQ
1:10 AM
0
Q: Curl of electric field

pasaba por aquiRelated: How is the curl of the electric field possible? According to my information: $$\nabla \times \frac{\hat{r}}{{|\mathbf{r}|}^2} = 0 $$ for all $\mathbf{r}$ ( including $\mathbf{r}=0$; compare with $\nabla \frac{\hat{r}}{{|\mathbf{r}|}^2} = 4 \pi \delta(|\mathbf{r}|)$ that is zero excep...

 
 
2 hours later…
HNQ
3:12 AM
3
Q: Conservation of momentum in photon-atom collision

GoPhysIs this explanation correct: When a photon with the appropriate energy hits an atom, the electron will make a transition from the ground state to a excited state. This will make the potential energy of the atom higher. Also, momentum is conserved, and the velocity of the atom will change in the ...

 
 
14 hours later…
HNQ
5:05 PM
4
Q: Earth magnetic field space elevator. No cable

Alexander SpacelifterI have an idea that the space elevator can be build in the following conditions: Not a classic theory. No cable. No Geostatic orbit. Not equator platform position The position is north magnetic pole - Antarctica. The lifting force is Earth magnetic field. The lift design is a huge ring (more th...

 

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