Recent content by Perpendicular

I know that each plate feels the field due to the other plate alone. I just want to derive that via energy stored in the electric field, and this seems to be impossible without the fringe field which is in turn very hard to numerically figure out. Ignoring it, I get F = zero which is absurd.

Because at points not too far off to the edge, or corners, the field due to each plate can be approximated as charge density/2e0. They act in opposite directions. I now realize though, this probably implies the fringe field is non-negligible in this case..

Hello, I am facing a paradox, well it seems like one, resolving the interaction force between two equally charged plates each bearing a positive charge. Let us assume this as Q, and plates having area A. On one hand , we can claim the force = Q^2/2Ae0 where e0 is the vacuum permittivity...

Flux at a point would be referring to how the texts deal with the situation of calculating flux when a point charge is present on the surface.

Hmm. Could you tell me where I could look up the question of flux at a point via a point charge ? I have Griffith's and Jackson's.

Why shouldn't flux AT a point be zero, though ? The outward and inward normal aren't distinct there. You can't pick one , so you must pick both, and hence whatever flux you have for one should perfectly cancel the other. Yeah, the individual quantities are undefined , but that does not...

I ended up concluding that flux AT the point should be zero, because there, infinite field components in all directions cancel out to give zero field, kind of like an eye of the storm. I dislike the sphere argument. Points aren't spheres. Points are points. So should it be, flux exists, and...

Consider a point charge q at the vertex of an arbitrary cube. If asked to consider the flux the cube experiences, q/8epsilon seems a natural answer, by constructing seven more such cubes to create an overall cube of 8 times the volume with q at its center. But, this doesn't make sense to me...

Hi, I am trying to work with the problem of keeping a solid body at equilibrium over an orifice. To see what I mean ( not necessarily a sphere could be a cube or something like that as well ) please look at the image I have attached. I am trying to work with the sphere case first and then...

So basically one component of N does work while the other cancels that work out ?

The body rotates clockwise and the normal force applies a clockwise torque which must do some work over the angular displacement, right ? And from the CM frame, where else would you even get torque ? after all work = torque.angular change as well.

well it is but I'm confused regarding what to do with the normal force N...supposing some angular movement theta I am thinking of expressing the torque due to N as some trigonometric function and then integrating over dtheta to get work done due to torque by normal force. Then I think the eqn...

Suppose we have a rod standing vertically and then slightly disturbed so it begins to fall. After it falls through some height or angle assuming a clockwise rotational fall I can see that the left end is sliding on the surface ( for simplicity I'm ignoring friction ) horizontally. Here I assume...

As for (e) consider that you have a final change in KE, as well as the masses. You can now plug that into solve for velocity.

Consider the total energy over time which is a constant. Hence change in PE must balance out change in KE. The rest is obvious.