0
votes
2answers
35 views

Could Charles-Augustin de Coulomb measure the charge in Coulombs?

Did Charles-Augustin de Coulomb know: Coulomb's constant Coulomb (as a unit) if not then what was the first time it was measured?
-3
votes
0answers
29 views

Charge by Induction [on hold]

For example, Initially, there are two metal sphere touching each other and the ball on the left has a charge of +5q, while the other is neutral. Then a rod with charge -3q is brought near the left ...
1
vote
4answers
178 views
+50

Charge distribution on plates

$A,B,C$ are $3$ identical metallic plates. Initially, charges $Q$, $4Q$ and $2Q$ were given to $A$,$B$ and $C$ respectively. Find final charge distributions when $B$ was earthed and $A$ and $C$ were ...
0
votes
0answers
23 views

Electrostatic pressure and charge [closed]

I've become a bit stuck on a question involving the charge transferred to a soap bubble as it's momentarilly connected to a potential V. I calculated the pressure difference between the atmosphere ...
0
votes
0answers
18 views

Question regarding 2 conducting spheres connected by a long fine line (electric potentional)

I'm having a bit of trouble understanding a pretty simple issue. Assuming I have 2 conducting spheres uniformly charged connected by a long fine line (as shows in the added photo) and im being asked ...
3
votes
2answers
342 views

What is charge actually? How to define it? [closed]

Is charge of something for (e.g.) an electron related to electromagnetic space if it exists due to energy, due to which it may have mass? I don't know about quantum mechanics or advanced particle ...
7
votes
1answer
650 views

Solve my confusion about electrons?

When a glass rod is rubbed with a silk cloth, both get charged: The silk gets positively charged and the rod gets negatively charged. My question is the following: How/why do these objects return to ...
-1
votes
1answer
41 views

Attraction and repulsion of charge? [duplicate]

Why do like charges on identical bodies cause a repulsion and unlike charges cause an attraction?
1
vote
2answers
48 views

How does particles gain electrical charges and repel each others? (electrostatic stabilization)

When I study electrostatic stabilization, I understand that the particles have same charge and thus repel others, this is how colloid is stabilize. But how does particles gain electrical charges and ...
0
votes
1answer
25 views

In what ratio does the charge distribute if a charge and uncharged body touch each other?

Lets say a large charged body has $n$ elementary charges and is brought in contact with a small uncharged body. When the charge distributes, does it distribute in the ratio of number of atoms or each ...
0
votes
3answers
44 views

Why leaf of electrometer doesn't repel each other in water?

Why leaf of electrometer doesn't repel each other in water? Normal electrometer filled with air will repel like it should do for electrostatic demonstration, but what if filled with water instead or ...
3
votes
2answers
72 views

Charge distribution on conductors?

You have seen that the excess charge on an isolated conductor moves entirely to the conductor’s surface. However, unless the conductor is spherical, the charge does not distribute itself uniformly. ...
1
vote
1answer
39 views

Does charge of a metal charged by induction determine by which ends of the metal is grounded to?

Does charge of a metal charged by induction determine by which part of the metal is ground to? I draw a diagram to make it simple to understand: Right diagram: When ground is touched with the ...
0
votes
3answers
41 views

Does corona discharge charged insulator?

Does corona discharge charged insulator? I draw a diagram to make it simpler to understand. Electrons form negative side is accelerated due to electric field and accumulate on insulator surface. Gas ...
1
vote
1answer
24 views

Does higher voltage and plate area cause more separation between leaves in electroscope?

Does higher voltage cause more separation between leaves in electroscope? Will higher voltage and plate area attract more charge since Q = CV.
2
votes
1answer
65 views

What determines how much electrical charge an object can hold?

What determines how much electrical charge an object can hold? Does increase voltage force more electrical charge to be store in an object (Van de Graaff generator), since electric field increase as ...
1
vote
5answers
328 views

How would charge distribute if electrons were balls?

In a conductor, any excess charge will distribute itself evenly over the surface of the conductor. Because of quantum mechanics, this is possible with small charges (i.e. 1e). But if electrons were ...
2
votes
1answer
229 views

Finding electric field between overlapping surfaces [closed]

The problem is: A sphere with radius R is centered at the origin, an infinite cylinder with radius R has its axis along the z axis, and an infinite slab with thickness 2R lies between the planes ...
1
vote
1answer
47 views

Electric potential and movement of charges

If electric field is not present does that mean that charges achieve condition of electrostatics I.e, charges are stationary ? But we say that stationary charge can produce electric field. I read ...
1
vote
0answers
66 views

Electric potential on a uniformly charged tube

A hollow cylinder, with no top or bottom, of radius $R$ and length $L$ is uniformly charged with density $\sigma>0$. I have to find the point on space where a point charge $q>0$ has to be drawn ...
1
vote
0answers
33 views

Does all electrical insulator can be electrostatically charged?

Does all electrical insulator can be electrostatically charged, or insulator with only dielectric property can? Thank you.
1
vote
2answers
62 views

Can a liquid insulator be electrically charged by touching a charged conductor?

Can a liquid insulator be electrically charged by touching a charged conductor? I understand that solid insulator will only be charge on the surface where it is touch, but the case is different ...
0
votes
0answers
82 views

Force and Energy of interaction of conducting sphere and point charge

A completely isolated neutral conducting sphere of radius $R$ is kept such that its center is at a distance of $r\left(>R\right)$ from a point charge $+Q$. How can I find the force of ...
3
votes
4answers
293 views

Conductors and their charge?

Why does excess positive charge stay on the surface of a conductor? This is what I understood from: How does positive charge spread out in conductors? and other resources on the web: If there is a ...
0
votes
2answers
175 views

Does any object placed in an electric field change the electric field?

Lets say I have a point charge of magnitude $+q$, All around it I would have a symmetric radial electric field. Now if I place a neutral object lets say a sphere (doesn't matter insulating or ...
0
votes
0answers
45 views

Why is it easier to **just** rub charge onto something?

We have all experienced the mild zaps caused by static build up of charges due to triboelectric effect Electric field strenth of air = $ 3 × 10^6 Vm^{-1} $ Now, suppose we feel the zaps after ...
1
vote
1answer
179 views

Surface charge density relation with the radius of curvature at the surface of a conductor [closed]

In a text book it was given that the surface charge density of a conductor at a particular region on its surface is inversely proportional to the radius of curvature at that region. I didn't ...
1
vote
2answers
157 views

How is electric flux related to permittivity?

How is Gauss' law related to permittivity? I know that it equals $1/\epsilon_0$ times the magnitude of the charge enclosed. But, I'm unable to understand what it actually means. Can someone ...
0
votes
1answer
60 views

Reduced charge for attracting electrons?

The reduced mass in the two body problem is $\mu= \cfrac{m_1 m_2}{m_1 + m_2}$. Is there any analog to this with interacting charged particles (or at least that is of use somewhere in physics)? I have ...
3
votes
1answer
122 views

Local nature of a surface charge density

Boundary S of a cavity in a very large (perfect) conductor is a connected compact (smooth) surface. A positive point charge +q is placed inside this cavity. From Gauss' law we know that the total ...
2
votes
2answers
559 views

When can a surface charge density exist?

In my syllabus about electromagnetism, they state: "This surface charge density will not always be present, e.g. when considering two non-conducting dielectrics such surface charge density remains ...
4
votes
2answers
186 views

Why do clouds appear black?

I have noticed clouds appearing black during rain. But I don't know what makes clouds to acquire that colour. This phenomenon doesn't appear every rainfall. There has to be distinction to white ...
0
votes
2answers
237 views

What happened to potential energy?

I was learning how charge can be virtue of a body's potential energy.Meanwhile,I was hung by this question. [gravitational and other forces except coulombic,are assumed to be not acting on the ...
0
votes
2answers
342 views

How do I express the interaction energy between two charged spheres?

Consider two identical insulating spheres each with radius $R$ and uniform charge $Q$ through their volume. They are separated from their centers by a distance of $d>2R$. Here is my general ...
4
votes
2answers
195 views

Will there be any force of attraction or repulsion between an electrified body and a non-electrified body?

Up to my knowledge an electrified (charged) body can attract a non-electrified (neutral) body. I thought this because, when we bring a charged (suppose negatively charged) body near a neutral one. ...
9
votes
3answers
446 views

How would charge be distributed in charged conductors if the Coulomb law was not ${1}/{r^2}$?

Would the excess charge on a conductor move to surface until the electric field inside become zero if the Coulomb law was for example $\frac{1}{r^3}$? If yes, would the distribution $\sigma(x,y)$ be ...
5
votes
1answer
194 views

Density of repulsive particles on a disk?

NB: the external circle (where particle or water is in it) is fixed ! It's a 2D theoretical problem (just for understand something in particular). Here, no gravity, no temperature. I put in a disk a ...
1
vote
1answer
79 views

Where do electrical charges go, on a nonconductor dielectric when we make it charged?

My question is about electrically nonconductor dielectrics. We know such materials don't possess free charges.They have atoms bound together and every atom has specific numbers of electrons turning ...
0
votes
1answer
541 views

Electric field outside a hollow cylindrical conducting shell [closed]

Imagine that a point charge $+Q$ is located at radius $R$ and height $z=0$ inside of an infinitely long conducting cylinder shell of inner radius $a>R$ and outer radius $b$. From what we know of ...
0
votes
1answer
63 views

About electrostatic induction

when we approach a charged rod (+) to a neutral metal rod ( not touching) a number of electrons to that side ( lets call it side B) negating the effect of the introduced electric field, reaching ...
3
votes
2answers
377 views

Potential of arbitrary charge distribution

Imagine this: You have a sphere of air where you have no charge and around this sphere you have a charge distribution $\rho(r,\theta,\phi)$. (For instance, this could be ...
0
votes
0answers
190 views

Electric field of uniformly charged spherical cap?

I was wondering what the electric field of a uniformly charged spherical cap is? Thereby I am referring to a spherical shell that was sliced into two pieces and we are only looking at one part of it. ...
1
vote
1answer
92 views

Dielectric modification of electrostatic equations?

I have learnt that in cases of electrostatic fields inside a dielectric of any source charge, the field is reduced by a factor of K( if K, the dielectric "constant", is taken everywhere to be same). ...
0
votes
1answer
154 views

Electrons drift velocity and capacitors

My friend said this to me and just want to make sure this is right " when we connect the a battery to a LED and the 2 poles are connected, electrons flow from the (-) to the (+) but with very low ...
1
vote
1answer
70 views

How can we consider charge to be continuous? [duplicate]

In electrostatics, we usually consider charge to be continuous on any body, to calculate the electric field of the body. For eg. I had proved the Shell Theorem taking an infinitesimal charge of $dq$ ...
0
votes
1answer
395 views

Charging by induction (and grounding)?

The very familiar phenomenon of charging by induction includes bringing a charged object near an uncharged sphere to induce a separation of charges in it and then grounding the charge (same as the ...
1
vote
1answer
100 views

Dipole moment dilemmas

Dipole moment for a couple of charges, say q and -q, separated by a distance 'd' is given by 'qd' But what is for dissimilar magnitudes,say (q and 2q) or (q and -2q)? And are dipole moment defined ...
0
votes
2answers
146 views

Field lines question

A friend of mine asked me this question, that is asked in an entrance examination. It shouldn't be that difficult, but I fail to find a rigorous answer for it. The figure shows three charges, that ...
0
votes
1answer
113 views

How can the accurate value of electric field intensity be calculated?

When we calculate electric field intensity for a point charge at any point inside electric field the field intensity is $E = F/q$ where $F$ is the force acting on charge $q$. In this case, the charge ...
4
votes
1answer
489 views

How much negative charge do I accumulate by touching the earth?

The Earth carries a negative electric charge of roughly 500 thousand Coulombs (according to different sources I've seen). If I touch the Earth I should therefore pick up some of this electric charge ...