A law in Classical Electromagnetism and Newtonian Gravity.

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Why we cannot use Gauss's Law to find the Electric Field of a finite-length charged wire?

One of my physics books has a nice example on how to use Gauss's Law to find the electric field of a long (infinite) charged wire. However, at the very end of the example, the author ends by saying ...
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Infinitely charged wire and Differential form of Gauss' Law

I have tried calculating the potential of a charged wire the direct way. If lambda is the charge density of the wire, then I get $$\phi(r) = \frac{\lambda}{4 \pi \epsilon_0 r} \int_{-\infty}^\infty ...
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Calculating capacitance of arbitrary plate shape and arrangement.

Looking for suggestions on how to approach calculating the capacitance of a capacitor where the plates have an arbitrary shape. I've seen derivations of capacitance for a few highly symmetric ...
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Electric fields in/around conductors

So according to my notes, the field inside a conductor is zero. But what, exactly, is meant by inside? I think we are in electrostatics for the purpose of this question. The reason it is zero is ...
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“Find the net force the southern hemisphere of a uniformly charged sphere exerts on the northern hemisphere”

This is Griffiths, Introduction to Electrodynamics, 2.43, if you have the book. The problem states Find the net force that the southern hemisphere of a uniformly charged sphere exerts on the ...
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Charge Distribution on a Parallel Plate Capacitor

If a parallel plate capacitor is formed by placing two infinite grounded conducting sheets, one at potential $V_1$ and another at $V_2$, a distance $d$ away from each other, then the charge on either ...
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Scaling of Static Electric Field

The electric field of a point charge goes like $\displaystyle\frac{1}{r^2}$ The electric field of an infinite line goes like $\displaystyle\frac{1}{s}$ The electric field of an infinite plane is ...
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Electric Flux Density - Ring Charge

A ring placed along $y^{2}$ + $z^{2}$ = 4, x = 0 carries a uniform charge of 5 $\mu$C/m. Find D at P(3,0,0) Should I be using Gauss's Law to solve this problem? I was considering using a spherical ...
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Gauss' law - changes in the magnitude of E field inside the closed surface

Gauss's law says that the flux through a closed surface which contains neither a sink nor a source will be zero. It's quite clear that all field lines will have to exit somehow, but the strength of ...
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Electric field due to nonconducting plastic sheets [closed]

Two very large, nonconducting plastic sheets, each 10.0 cm thick, carry uniform charge densities $\sigma_1, \sigma_2, \sigma_3$ and $\sigma_4$ on their surfaces (the four surfaces are in the ...
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Gauss's Law vs Newton's Law

This is thought experiment. I couldn't get a good answer because I keep getting negative mass. Gauss's Law say that eletric field is proportional to charge, how much charged is enclosed. Newton's ...
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Gauss' law giving zero field where field is not zero?

Two plastic sheets with charged densities as shown: I'm trying to find the field at $B$. I obtained the correct answer by adding up the fields created by each charge density. But I realized that ...
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Electric field outside a capacitor

I know that the electric field outside of a capacitor is 0 and I know it is easy to calculate using Gauss's law. We create cylindrical envelope that holds the same amount of charges (of opposite ...
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Does Coulomb's Law, with Gauss's Law, imply the existence of only three spatial dimensions?

Coulomb's Law states that the fall-off of the strength of the electrostatic force is inversely proportional to the distance squared of the charges. Gauss's law implies that a the total flux through a ...