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Author Integrating line charges
anon54325345@googlemail.com

2007-09-12, 5:25 pm

The question I am asking is about a variation on integrating a typical
line charge.

The charged line lays on the x-axis(beginning at x=0), which has a
length "L". Their is a test charge point, also on the x-axis at a
distance "D" from the line(or L+D from the origin)

I am quite familiar with how to set up the integral to find the force
or field on the test charge for a UNIFORM charge distribution on the
charged line. (dq = lambda * dx)

My problem however is that my linear charge density isn't uniform, it
is a function of x with an unknown constant. (lambda = constant * x)

Can anyone point me in the right direction, or at least to a resource
that might have similar solved problems?

Thanks

Eric Gisse

2007-09-12, 8:25 pm

On Wed, 12 Sep 2007 14:25:41 -0700, anon54325345@googlemail.com wrote:

>The question I am asking is about a variation on integrating a typical
>line charge.
>
>The charged line lays on the x-axis(beginning at x=0), which has a
>length "L". Their is a test charge point, also on the x-axis at a
>distance "D" from the line(or L+D from the origin)
>
>I am quite familiar with how to set up the integral to find the force
>or field on the test charge for a UNIFORM charge distribution on the
>charged line. (dq = lambda * dx)
>
>My problem however is that my linear charge density isn't uniform, it
>is a function of x with an unknown constant. (lambda = constant * x)
>
>Can anyone point me in the right direction, or at least to a resource
>that might have similar solved problems?


Do you know how to do an integral?

>
>Thanks

PD

2007-09-13, 3:25 am

On Sep 12, 4:25 pm, anon54325...@googlemail.com wrote:
> The question I am asking is about a variation on integrating a typical
> line charge.
>
> The charged line lays on the x-axis(beginning at x=0), which has a
> length "L". Their is a test charge point, also on the x-axis at a
> distance "D" from the line(or L+D from the origin)
>
> I am quite familiar with how to set up the integral to find the force
> or field on the test charge for a UNIFORM charge distribution on the
> charged line. (dq = lambda * dx)
>
> My problem however is that my linear charge density isn't uniform, it
> is a function of x with an unknown constant. (lambda = constant * x)


So integrate, but now you have an integrand that contains a factor
c*x*dx. You know how to integrate c*x*dx?

>
> Can anyone point me in the right direction, or at least to a resource
> that might have similar solved problems?
>
> Thanks



Jim Black

2007-09-13, 3:25 am

On Wed, 12 Sep 2007 14:25:41 -0700, anon54325345@googlemail.com wrote:

> The question I am asking is about a variation on integrating a typical
> line charge.
>
> The charged line lays on the x-axis(beginning at x=0), which has a
> length "L". Their is a test charge point, also on the x-axis at a
> distance "D" from the line(or L+D from the origin)
>
> I am quite familiar with how to set up the integral to find the force
> or field on the test charge for a UNIFORM charge distribution on the
> charged line. (dq = lambda * dx)
>
> My problem however is that my linear charge density isn't uniform, it
> is a function of x with an unknown constant. (lambda = constant * x)
>
> Can anyone point me in the right direction, or at least to a resource
> that might have similar solved problems?
>
> Thanks


If you've been given the total charge of the line, you can use that
information to figure out the value of the constant.

The charge of an infintesimal piece of the line is still

dq = lambda * dx,

even if lambda is a function of x. Use dq as the charge in Coulomb's law
to get the contribution of that infintesimal piece to the electric field,
and integrate.
Roy

2007-09-13, 3:25 am

From: anon54325345@googlemail.com
The question I am asking is about a variation on integrating a typical
line charge.
The charged line lays on the x-axis(beginning at x=0), which has a
length "L". Their is a test charge point, also on the x-axis at a
distance "D" from the line(or L+D from the origin)
I am quite familiar with how to set up the integral to find the force or
field on the test charge for a UNIFORM charge distribution on the
charged line. (dq = lambda * dx)
My problem however is that my linear charge density isn't uniform, it is
a function of x with an unknown constant. (lambda = constant * x)
Can anyone point me in the right direction, or at least to a resource
that might have similar solved problems?
Thanks


*** I'm just the Idiot around here but, what is this for ?

It's sounds to me like you would like to see a formula that describes
the practical uses for an ac power line....with respect to Charge.

This formulation could be in realmode or spectrum quantities but for
practical purposes applied to elc.eng. we could look at transformer
specs and diverse power supply designs and with books and terms I'd have
it for you in a matter of days....but that's not my job If you want
the more scientific approach with Charge Physics - good luck., I charge
more for Scientific Analisys ... as you should..

Roy Q.T.
Urban Technician
[I don't make em, I just fix em]

Roy

2007-09-13, 3:25 am

Wed, Sep 12, 2007, 4:55pm (EDT-4) From: jowr.pi.nospam@gmail-nospam.com
(Eric=A0Gisse)
On Wed, 12 Sep 2007 14:25:41 -0700, anon54325345@googlemail.com wrote:

The question / integrating a typical line charge.

The charged line lays on the x-axis(beginning at x=3D0), which has a
length "L". Their is a test charge point, also on the x-axis at a
distance "D" from the line(or L+D from the origin)


UNIFORM charge distribution on the charged line.
(dq =3D lambda * dx)

My problem however is that my linear charge density isn't uniform, it is
a function of x with an unknown constant. (lambda =3D constant * x)
Can anyone point etc etc etc...

No Uniform Charge?
go with electron volts

& (lambda =3D constant * x)

It becomes something like
C =3D (phase angle * d)

If phase angle is lambda
C=3D (lambda x 120/240 *d)
where d =3D conductor size & length


Roy Q.T.
Urban Technician
[I don't make em, I just fix em]

Roy

2007-09-13, 3:25 am

Perhaps a VA - Volt/Amp formulation is more pratical for line charge
applications - let's see what the other idiots have to say.

All I need to know is what the hell you want it for ?

=AEoy UL Approved

Salmon Egg

2007-09-13, 5:25 pm

On 9/12/07 2:25 PM, in article
1189632341.245362.74330@y42g2000hsy.googlegroups.com,
"anon54325345@googlemail.com" <anon54325345@googlemail.com> wrote:

> The question I am asking is about a variation on integrating a typical
> line charge.
>
> The charged line lays on the x-axis(beginning at x=0), which has a
> length "L". Their is a test charge point, also on the x-axis at a
> distance "D" from the line(or L+D from the origin)
>
> I am quite familiar with how to set up the integral to find the force
> or field on the test charge for a UNIFORM charge distribution on the
> charged line. (dq = lambda * dx)
>
> My problem however is that my linear charge density isn't uniform, it
> is a function of x with an unknown constant. (lambda = constant * x)
>
> Can anyone point me in the right direction, or at least to a resource
> that might have similar solved problems?
>
> Thanks
>

Find the potential, by integrating the charge. Then you can take gradients
to find field strength of electrical force.

Bill
--
Iraq: About three Virginia Techs a month

Charles Perry

2007-09-13, 8:25 pm


"Roy" <ROYKEY@webtv.net> wrote in message
news:4564-46E8D5C4-234@storefull-3254.bay.webtv.net...
Perhaps a VA - Volt/Amp formulation is more pratical for line charge
applications - let's see what the other idiots have to say.

All I need to know is what the hell you want it for ?

Žoy UL Approved
-------------------------------

I read your replies and none of them were of any value. Why do you bother
to post to threads of which you have no knowledge.

Charles Perry P.E.


Roy

2007-09-13, 8:25 pm


Date: Thu, Sep 13, 2007, 7:48pm
From: pipesandtobacco@hotmail.com (Charles=A0Perry)
"Roy" <ROYKEY@webtv.net> wrote in message
news:4564-46E8D5C4-234@storefull-3254.bay.webtv.net... Perhaps a VA -
Volt/Amp formulation is more pratical for line charge applications -
let's see what the other idiots have to say.
All I need to know is what the hell you want it for ?
=AEoy UL Approved
-------------------------------
I read your replies and none of them were of any value. Why do you
bother to post to threads of which you have no knowledge.
Charles Perry P.E.

I was out of line using Idiot.
[they throw it around too much in here]

short answer: I Have The Time....

Since you're the pro, have it your way., but I may have to deal with it
down the line...Then again you don't know what I know, or what he wants
this integrated for. I may be part of an intrinsic system or like you
say, of no value to this group at all.

Thanks for you concern,

Roy Q. T.
E. E.Technician

ChairmanOfTheBored

2007-09-13, 9:25 pm

On Thu, 13 Sep 2007 01:21:13 -0400, ROYKEY@webtv.net (Roy) wrote:

>Wed, Sep 12, 2007, 4:55pm (EDT-4) From: jowr.pi.nospam@gmail-nospam.com
>(Eric_Gisse)
>On Wed, 12 Sep 2007 14:25:41 -0700, anon54325345@googlemail.com wrote:
>
>The question / integrating a typical line charge.
>
>The charged line lays on the x-axis(beginning at x=0), which has a
>length "L". Their is a test charge point, also on the x-axis at a
>distance "D" from the line(or L+D from the origin)
>
>
>UNIFORM charge distribution on the charged line.
>(dq = lambda * dx)
>
>My problem however is that my linear charge density isn't uniform, it is
>a function of x with an unknown constant. (lambda = constant * x)
>Can anyone point etc etc etc...
>
>No Uniform Charge?
>go with electron volts
>
>& (lambda = constant * x)
>
>It becomes something like
>C = (phase angle * d)
>
>If phase angle is lambda
>C= (lambda x 120/240 *d)
>where d = conductor size & length
>
>


You're an idiot.


>Roy Q.T.
>Urban Technician
>[I don't make em, I just fix em]


No, you don't, and no you are not.
ChairmanOfTheBored

2007-09-13, 9:25 pm

On Thu, 13 Sep 2007 01:11:58 -0400, ROYKEY@webtv.net (Roy) wrote:

>From: anon54325345@googlemail.com
>The question I am asking is about a variation on integrating a typical
>line charge.
>The charged line lays on the x-axis(beginning at x=0), which has a
>length "L". Their is a test charge point, also on the x-axis at a
>distance "D" from the line(or L+D from the origin)
>I am quite familiar with how to set up the integral to find the force or
>field on the test charge for a UNIFORM charge distribution on the
>charged line. (dq = lambda * dx)
>My problem however is that my linear charge density isn't uniform, it is
>a function of x with an unknown constant. (lambda = constant * x)
>Can anyone point me in the right direction, or at least to a resource
>that might have similar solved problems?
>Thanks
>
>
>*** I'm just the Idiot around here but, what is this for ?
>
>It's sounds to me like you would like to see a formula that describes
>the practical uses for an ac power line....with respect to Charge.
>
>This formulation could be in realmode or spectrum quantities but for
>practical purposes applied to elc.eng. we could look at transformer
>specs and diverse power supply designs and with books and terms I'd have
>it for you in a matter of days....but that's not my job If you want
>the more scientific approach with Charge Physics - good luck., I charge
>more for Scientific Analisys ... as you should..
>


You're a complete dope.
ChairmanOfTheBored

2007-09-13, 9:25 pm

On Thu, 13 Sep 2007 02:16:36 -0400, ROYKEY@webtv.net (Roy) wrote:

>Perhaps a VA - Volt/Amp formulation is more pratical for line charge
>applications - let's see what the other idiots have to say.


You are the ONLY idiot.
>
>All I need to know is what the hell you want it for ?
>
>Žoy UL Approved


Your sign offs prove it.
ChairmanOfTheBored

2007-09-14, 3:25 am

On Thu, 13 Sep 2007 20:58:52 -0400, ROYKEY@webtv.net (Roy) wrote:

>
>Date: Thu, Sep 13, 2007, 7:48pm
>From: pipesandtobacco@hotmail.com (Charles_Perry)
>"Roy" <ROYKEY@webtv.net> wrote in message
>news:4564-46E8D5C4-234@storefull-3254.bay.webtv.net... Perhaps a VA -
>Volt/Amp formulation is more pratical for line charge applications -
>let's see what the other idiots have to say.
>All I need to know is what the hell you want it for ?
>Žoy UL Approved
>-------------------------------
>I read your replies and none of them were of any value. Why do you
>bother to post to threads of which you have no knowledge.
>Charles Perry P.E.
>
>I was out of line using Idiot.
>[they throw it around too much in here]


They who, idiot?
>
>short answer: I Have The Time....
>
>Since you're the pro, have it your way., but I may have to deal with it
>down the line...Then again you don't know what I know, or what he wants
>this integrated for. I may be part of an intrinsic system or like you
>say, of no value to this group at all.
>
>Thanks for you concern,


No one is concerned with or about a dope like you.
>
>Roy Q. T.
>E. E.Technician



Bullshit.
LinkBot





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