Why is electric field inside a cavity of a non-conducting sphere not zero? [closed]Net flux through insulating cylinderElectric Field from charged sphere within another charged sphere does not reinforce?Gauss Law Not Working Inside Cavityelectric field inside a conducting bodyWhat is the electric field intensity inside a conducting sphere when charges are asymetrically distributed over the surface?For a point charge enclosed by a thin spherical conducting shell, at all points in hollow part of resulting sphere, can electric field be non-zero?Why is the electric field inside the hole non-zero?Electric field related to conducting materials containing charge containing cavityPoint charge inside hollow conducting sphereAre charges outside a conducting shell relevant to electric field inside the shell?
How do I reattach a shelf to the wall when it ripped out of the wall?
Re-entry to Germany after vacation using blue card
How to limit Drive Letters Windows assigns to new removable USB drives
Check if a string is entirely made of the same substring
What is the optimal strategy for the Dictionary Game?
Critique of timeline aesthetic
Contradiction proof for inequality of P and NP?
Don’t seats that recline flat defeat the purpose of having seatbelts?
Rivers without rain
How exactly does Hawking radiation decrease the mass of black holes?
How could Tony Stark make this in Endgame?
Usage of 万 (wàn): ten thousands or just a great number?
How does Captain America channel this power?
How do I produce this Greek letter koppa: Ϟ in pdfLaTeX?
Multiple options vs single option UI
Why do games have consumables?
Does any yogic siddhi let a human to be simultaneously present at two different places physically?
Why did some of my point & shoot film photos come back with one third light white or orange?
Could the terminal length of components like resistors be reduced?
can anyone help me with this awful query plan?
basic difference between canonical isomorphism and isomorphims
Is the claim "Employers won't employ people with no 'social media presence'" realistic?
How much cash can I safely carry into the USA and avoid civil forfeiture?
What to do with someone that cheated their way through university and a PhD program?
Why is electric field inside a cavity of a non-conducting sphere not zero? [closed]
Net flux through insulating cylinderElectric Field from charged sphere within another charged sphere does not reinforce?Gauss Law Not Working Inside Cavityelectric field inside a conducting bodyWhat is the electric field intensity inside a conducting sphere when charges are asymetrically distributed over the surface?For a point charge enclosed by a thin spherical conducting shell, at all points in hollow part of resulting sphere, can electric field be non-zero?Why is the electric field inside the hole non-zero?Electric field related to conducting materials containing charge containing cavityPoint charge inside hollow conducting sphereAre charges outside a conducting shell relevant to electric field inside the shell?
$begingroup$
Consider a charged non conducting solid sphere of uniform charge density, and it as hole of some radius at the centre.
Now suppose I apply Gauss law.
As there is no charge inside the cavity, no charge is enclosed by Gaussian sphere, so electric flux is zero, hence electric field is zero.
But this is not true according to sources like this, textbook etc..
What am I missing here?
My question about how to have nonzero field in a region where the flux through the boundary of the region vanish? As mentioned by– rob
electrostatics electric-fields charge gauss-law
$endgroup$
closed as unclear what you're asking by my2cts, GiorgioP, ZeroTheHero, Jon Custer, John Rennie Mar 25 at 17:38
Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.
|
show 2 more comments
$begingroup$
Consider a charged non conducting solid sphere of uniform charge density, and it as hole of some radius at the centre.
Now suppose I apply Gauss law.
As there is no charge inside the cavity, no charge is enclosed by Gaussian sphere, so electric flux is zero, hence electric field is zero.
But this is not true according to sources like this, textbook etc..
What am I missing here?
My question about how to have nonzero field in a region where the flux through the boundary of the region vanish? As mentioned by– rob
electrostatics electric-fields charge gauss-law
$endgroup$
closed as unclear what you're asking by my2cts, GiorgioP, ZeroTheHero, Jon Custer, John Rennie Mar 25 at 17:38
Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.
$begingroup$
So let me clarify. There is a sphere with a uniform volumetric charge density, and you cut out a cavity that has no charge in it?
$endgroup$
– noah
Mar 23 at 12:07
$begingroup$
Yes that is correct interpretation
$endgroup$
– user72730
Mar 23 at 14:55
$begingroup$
closely related to physics.stackexchange.com/questions/461620/… Simply because the flux is $0$ doesn't mean the field is $0$.
$endgroup$
– ZeroTheHero
Mar 23 at 20:45
$begingroup$
Please make this post self contained by giving an explicit formulation of the question rather than a YouTube link or reference to an unnamed textbook.
$endgroup$
– my2cts
Mar 24 at 10:19
$begingroup$
@ruakh But OP is clearly talking about a solid ball with some cavity in it, but calls it a sphere.
$endgroup$
– noah
Mar 24 at 11:01
|
show 2 more comments
$begingroup$
Consider a charged non conducting solid sphere of uniform charge density, and it as hole of some radius at the centre.
Now suppose I apply Gauss law.
As there is no charge inside the cavity, no charge is enclosed by Gaussian sphere, so electric flux is zero, hence electric field is zero.
But this is not true according to sources like this, textbook etc..
What am I missing here?
My question about how to have nonzero field in a region where the flux through the boundary of the region vanish? As mentioned by– rob
electrostatics electric-fields charge gauss-law
$endgroup$
Consider a charged non conducting solid sphere of uniform charge density, and it as hole of some radius at the centre.
Now suppose I apply Gauss law.
As there is no charge inside the cavity, no charge is enclosed by Gaussian sphere, so electric flux is zero, hence electric field is zero.
But this is not true according to sources like this, textbook etc..
What am I missing here?
My question about how to have nonzero field in a region where the flux through the boundary of the region vanish? As mentioned by– rob
electrostatics electric-fields charge gauss-law
electrostatics electric-fields charge gauss-law
edited Mar 25 at 17:10
user72730
asked Mar 23 at 11:51
user72730user72730
838
838
closed as unclear what you're asking by my2cts, GiorgioP, ZeroTheHero, Jon Custer, John Rennie Mar 25 at 17:38
Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.
closed as unclear what you're asking by my2cts, GiorgioP, ZeroTheHero, Jon Custer, John Rennie Mar 25 at 17:38
Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.
$begingroup$
So let me clarify. There is a sphere with a uniform volumetric charge density, and you cut out a cavity that has no charge in it?
$endgroup$
– noah
Mar 23 at 12:07
$begingroup$
Yes that is correct interpretation
$endgroup$
– user72730
Mar 23 at 14:55
$begingroup$
closely related to physics.stackexchange.com/questions/461620/… Simply because the flux is $0$ doesn't mean the field is $0$.
$endgroup$
– ZeroTheHero
Mar 23 at 20:45
$begingroup$
Please make this post self contained by giving an explicit formulation of the question rather than a YouTube link or reference to an unnamed textbook.
$endgroup$
– my2cts
Mar 24 at 10:19
$begingroup$
@ruakh But OP is clearly talking about a solid ball with some cavity in it, but calls it a sphere.
$endgroup$
– noah
Mar 24 at 11:01
|
show 2 more comments
$begingroup$
So let me clarify. There is a sphere with a uniform volumetric charge density, and you cut out a cavity that has no charge in it?
$endgroup$
– noah
Mar 23 at 12:07
$begingroup$
Yes that is correct interpretation
$endgroup$
– user72730
Mar 23 at 14:55
$begingroup$
closely related to physics.stackexchange.com/questions/461620/… Simply because the flux is $0$ doesn't mean the field is $0$.
$endgroup$
– ZeroTheHero
Mar 23 at 20:45
$begingroup$
Please make this post self contained by giving an explicit formulation of the question rather than a YouTube link or reference to an unnamed textbook.
$endgroup$
– my2cts
Mar 24 at 10:19
$begingroup$
@ruakh But OP is clearly talking about a solid ball with some cavity in it, but calls it a sphere.
$endgroup$
– noah
Mar 24 at 11:01
$begingroup$
So let me clarify. There is a sphere with a uniform volumetric charge density, and you cut out a cavity that has no charge in it?
$endgroup$
– noah
Mar 23 at 12:07
$begingroup$
So let me clarify. There is a sphere with a uniform volumetric charge density, and you cut out a cavity that has no charge in it?
$endgroup$
– noah
Mar 23 at 12:07
$begingroup$
Yes that is correct interpretation
$endgroup$
– user72730
Mar 23 at 14:55
$begingroup$
Yes that is correct interpretation
$endgroup$
– user72730
Mar 23 at 14:55
$begingroup$
closely related to physics.stackexchange.com/questions/461620/… Simply because the flux is $0$ doesn't mean the field is $0$.
$endgroup$
– ZeroTheHero
Mar 23 at 20:45
$begingroup$
closely related to physics.stackexchange.com/questions/461620/… Simply because the flux is $0$ doesn't mean the field is $0$.
$endgroup$
– ZeroTheHero
Mar 23 at 20:45
$begingroup$
Please make this post self contained by giving an explicit formulation of the question rather than a YouTube link or reference to an unnamed textbook.
$endgroup$
– my2cts
Mar 24 at 10:19
$begingroup$
Please make this post self contained by giving an explicit formulation of the question rather than a YouTube link or reference to an unnamed textbook.
$endgroup$
– my2cts
Mar 24 at 10:19
$begingroup$
@ruakh But OP is clearly talking about a solid ball with some cavity in it, but calls it a sphere.
$endgroup$
– noah
Mar 24 at 11:01
$begingroup$
@ruakh But OP is clearly talking about a solid ball with some cavity in it, but calls it a sphere.
$endgroup$
– noah
Mar 24 at 11:01
|
show 2 more comments
4 Answers
4
active
oldest
votes
$begingroup$
Just to add to what Noah said, the law says that the total flux through the surface is zero. To make this point clear, imagine a region of uniform electric field $vecE = E_0hatx$ along the x axis. Consider a cube of unit area faces with two of its opposite faces normal to the field. From the RHS of Gauss law we know that the flux has to be zero as there are no charges enclosed by the cube. The LHS says
$sum_n=1^6 vecEcdot vecA_n = E_0hatxcdothatx + E_0hatxcdot-hatx = 0$
Thus the flux is zero by explicit calculation as well. Remember that the electric field and area are vectors. So the relative directions are very important. If flux is zero all you can be sure of is that the extent of field lines entering is equal to that of exiting.
$endgroup$
add a comment |
$begingroup$
Gauss's Law only gives results for the integral over a whole, closed surface. This does not mean the electric field is zero. It simply means that all field lines entering the volume also exit it at some other point.
$endgroup$
add a comment |
$begingroup$
In the video the electric field lines are as shown in blue in the diagram below.
Let the edge of the cavity be the Gaussian surface which has no charge within it.
Consider small areas $Delta A$ on either side of the cavity as shown in the diagram in red.
Because of the symmetrical nature of the situation you can imagine that the electric flux entering the cavity through area $Delta A$ is the same as the electric flux leaving the area $Delta A$ on the right hand side.
This means that the net flux through those two surfaces is zero.
Doing the same for the whole Gaussian surface leads to the result that the net flux though the surface is zero commensurate with the fact that there is no charge within the surface.
$endgroup$
add a comment |
$begingroup$
The field of a uniformly charged shell is zero inside the shell in agreement with Gauss's law, unless there is an external field.
A uniformly charged sphere with a concentric spherical cavity is a concentric sum of such shells, so the field in the cavity vanishes.
$endgroup$
add a comment |
4 Answers
4
active
oldest
votes
4 Answers
4
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Just to add to what Noah said, the law says that the total flux through the surface is zero. To make this point clear, imagine a region of uniform electric field $vecE = E_0hatx$ along the x axis. Consider a cube of unit area faces with two of its opposite faces normal to the field. From the RHS of Gauss law we know that the flux has to be zero as there are no charges enclosed by the cube. The LHS says
$sum_n=1^6 vecEcdot vecA_n = E_0hatxcdothatx + E_0hatxcdot-hatx = 0$
Thus the flux is zero by explicit calculation as well. Remember that the electric field and area are vectors. So the relative directions are very important. If flux is zero all you can be sure of is that the extent of field lines entering is equal to that of exiting.
$endgroup$
add a comment |
$begingroup$
Just to add to what Noah said, the law says that the total flux through the surface is zero. To make this point clear, imagine a region of uniform electric field $vecE = E_0hatx$ along the x axis. Consider a cube of unit area faces with two of its opposite faces normal to the field. From the RHS of Gauss law we know that the flux has to be zero as there are no charges enclosed by the cube. The LHS says
$sum_n=1^6 vecEcdot vecA_n = E_0hatxcdothatx + E_0hatxcdot-hatx = 0$
Thus the flux is zero by explicit calculation as well. Remember that the electric field and area are vectors. So the relative directions are very important. If flux is zero all you can be sure of is that the extent of field lines entering is equal to that of exiting.
$endgroup$
add a comment |
$begingroup$
Just to add to what Noah said, the law says that the total flux through the surface is zero. To make this point clear, imagine a region of uniform electric field $vecE = E_0hatx$ along the x axis. Consider a cube of unit area faces with two of its opposite faces normal to the field. From the RHS of Gauss law we know that the flux has to be zero as there are no charges enclosed by the cube. The LHS says
$sum_n=1^6 vecEcdot vecA_n = E_0hatxcdothatx + E_0hatxcdot-hatx = 0$
Thus the flux is zero by explicit calculation as well. Remember that the electric field and area are vectors. So the relative directions are very important. If flux is zero all you can be sure of is that the extent of field lines entering is equal to that of exiting.
$endgroup$
Just to add to what Noah said, the law says that the total flux through the surface is zero. To make this point clear, imagine a region of uniform electric field $vecE = E_0hatx$ along the x axis. Consider a cube of unit area faces with two of its opposite faces normal to the field. From the RHS of Gauss law we know that the flux has to be zero as there are no charges enclosed by the cube. The LHS says
$sum_n=1^6 vecEcdot vecA_n = E_0hatxcdothatx + E_0hatxcdot-hatx = 0$
Thus the flux is zero by explicit calculation as well. Remember that the electric field and area are vectors. So the relative directions are very important. If flux is zero all you can be sure of is that the extent of field lines entering is equal to that of exiting.
answered Mar 23 at 12:52
user3518839user3518839
1866
1866
add a comment |
add a comment |
$begingroup$
Gauss's Law only gives results for the integral over a whole, closed surface. This does not mean the electric field is zero. It simply means that all field lines entering the volume also exit it at some other point.
$endgroup$
add a comment |
$begingroup$
Gauss's Law only gives results for the integral over a whole, closed surface. This does not mean the electric field is zero. It simply means that all field lines entering the volume also exit it at some other point.
$endgroup$
add a comment |
$begingroup$
Gauss's Law only gives results for the integral over a whole, closed surface. This does not mean the electric field is zero. It simply means that all field lines entering the volume also exit it at some other point.
$endgroup$
Gauss's Law only gives results for the integral over a whole, closed surface. This does not mean the electric field is zero. It simply means that all field lines entering the volume also exit it at some other point.
answered Mar 23 at 12:09
noahnoah
4,32311328
4,32311328
add a comment |
add a comment |
$begingroup$
In the video the electric field lines are as shown in blue in the diagram below.
Let the edge of the cavity be the Gaussian surface which has no charge within it.
Consider small areas $Delta A$ on either side of the cavity as shown in the diagram in red.
Because of the symmetrical nature of the situation you can imagine that the electric flux entering the cavity through area $Delta A$ is the same as the electric flux leaving the area $Delta A$ on the right hand side.
This means that the net flux through those two surfaces is zero.
Doing the same for the whole Gaussian surface leads to the result that the net flux though the surface is zero commensurate with the fact that there is no charge within the surface.
$endgroup$
add a comment |
$begingroup$
In the video the electric field lines are as shown in blue in the diagram below.
Let the edge of the cavity be the Gaussian surface which has no charge within it.
Consider small areas $Delta A$ on either side of the cavity as shown in the diagram in red.
Because of the symmetrical nature of the situation you can imagine that the electric flux entering the cavity through area $Delta A$ is the same as the electric flux leaving the area $Delta A$ on the right hand side.
This means that the net flux through those two surfaces is zero.
Doing the same for the whole Gaussian surface leads to the result that the net flux though the surface is zero commensurate with the fact that there is no charge within the surface.
$endgroup$
add a comment |
$begingroup$
In the video the electric field lines are as shown in blue in the diagram below.
Let the edge of the cavity be the Gaussian surface which has no charge within it.
Consider small areas $Delta A$ on either side of the cavity as shown in the diagram in red.
Because of the symmetrical nature of the situation you can imagine that the electric flux entering the cavity through area $Delta A$ is the same as the electric flux leaving the area $Delta A$ on the right hand side.
This means that the net flux through those two surfaces is zero.
Doing the same for the whole Gaussian surface leads to the result that the net flux though the surface is zero commensurate with the fact that there is no charge within the surface.
$endgroup$
In the video the electric field lines are as shown in blue in the diagram below.
Let the edge of the cavity be the Gaussian surface which has no charge within it.
Consider small areas $Delta A$ on either side of the cavity as shown in the diagram in red.
Because of the symmetrical nature of the situation you can imagine that the electric flux entering the cavity through area $Delta A$ is the same as the electric flux leaving the area $Delta A$ on the right hand side.
This means that the net flux through those two surfaces is zero.
Doing the same for the whole Gaussian surface leads to the result that the net flux though the surface is zero commensurate with the fact that there is no charge within the surface.
answered Mar 23 at 16:13
FarcherFarcher
52.5k340112
52.5k340112
add a comment |
add a comment |
$begingroup$
The field of a uniformly charged shell is zero inside the shell in agreement with Gauss's law, unless there is an external field.
A uniformly charged sphere with a concentric spherical cavity is a concentric sum of such shells, so the field in the cavity vanishes.
$endgroup$
add a comment |
$begingroup$
The field of a uniformly charged shell is zero inside the shell in agreement with Gauss's law, unless there is an external field.
A uniformly charged sphere with a concentric spherical cavity is a concentric sum of such shells, so the field in the cavity vanishes.
$endgroup$
add a comment |
$begingroup$
The field of a uniformly charged shell is zero inside the shell in agreement with Gauss's law, unless there is an external field.
A uniformly charged sphere with a concentric spherical cavity is a concentric sum of such shells, so the field in the cavity vanishes.
$endgroup$
The field of a uniformly charged shell is zero inside the shell in agreement with Gauss's law, unless there is an external field.
A uniformly charged sphere with a concentric spherical cavity is a concentric sum of such shells, so the field in the cavity vanishes.
edited Mar 24 at 10:16
answered Mar 23 at 12:24
my2ctsmy2cts
6,0092719
6,0092719
add a comment |
add a comment |
$begingroup$
So let me clarify. There is a sphere with a uniform volumetric charge density, and you cut out a cavity that has no charge in it?
$endgroup$
– noah
Mar 23 at 12:07
$begingroup$
Yes that is correct interpretation
$endgroup$
– user72730
Mar 23 at 14:55
$begingroup$
closely related to physics.stackexchange.com/questions/461620/… Simply because the flux is $0$ doesn't mean the field is $0$.
$endgroup$
– ZeroTheHero
Mar 23 at 20:45
$begingroup$
Please make this post self contained by giving an explicit formulation of the question rather than a YouTube link or reference to an unnamed textbook.
$endgroup$
– my2cts
Mar 24 at 10:19
$begingroup$
@ruakh But OP is clearly talking about a solid ball with some cavity in it, but calls it a sphere.
$endgroup$
– noah
Mar 24 at 11:01