classroom Van der graaff generator

[szczepan bialek]

https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt, combs, and rollers
invisibly combine to form an electrostatic device called a Continuously
Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle and flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*

 

[George Herold]

On Wednesday, May 18, 2016 at 4:33:52 AM UTC-4, szczepan bialek wrote:

https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt, combs, and rollers
invisibly combine to form an electrostatic device called a Continuously
Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle and flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*

Both? I'm not sure what the question is? Bill Beaty hangs out at SED, you can
ask him directly.

George H.

 

[Tom Biasi]

On 5/18/2016 5:34 AM, szczepan bialek wrote:

https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt, combs, and rollers
invisibly combine to form an electrostatic device called a Continuously
Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle and flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*



The sphere is positive and the comb at the bottom of the roller is negative.

 

[szczepan bialek]

"George Herold" <gherold@teachspin.com> napisał w wiadomości
news:d7387b92-438c-4a0d-a26a-50921e6f01ec@googlegroups.com...

On Wednesday, May 18, 2016 at 4:33:52 AM UTC-4, szczepan bialek wrote:
https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt, combs, and rollers
invisibly combine to form an electrostatic device called a Continuously
Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle and
flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*

Both? I'm not sure what the question is? Bill Beaty hangs out at SED,
you can
ask him directly.

Wiki and Bill Beaty describe the same device: "The standard classroom Van de
Graff machine contains no power supply."
In the whole world is probably milions such devices. All are the same.
The question is:
Is on the sphere of the standard classroom Van de Graff machine the excess
of electrons or the deficyt?
S*

 

[whit3rd]

On Wednesday, May 18, 2016 at 7:47:59 AM UTC-7, szczepan bialek wrote:

The question is:
Is on the sphere of the standard classroom Van de Graff machine the excess
of electrons or the deficyt?

The upper electrode is round. The lower electrode is half-round and has
feet. While it is usual for the lower electrode to be grounded (so it doesn't electrify the
floor or other nearby objects/persons), the two electrodes can be given any
polarity you want.

In research machines, there's bunches of ancillary stuff that controls the currents.
In a classroom-demo, it might be as simple as a pointy-thing versus a flat-thing
type of gas rectifier. The positive ions are gas molecules, the negative include
free electrons, so the point (where ions are generated by field emission) ) collects
only a few electrons: they're fast moving and attracted to the flat.

 

[Baron]

szczepan bialek prodded the keyboard with:

"George Herold" <gherold@teachspin.com> napisał w wiadomości
news:d7387b92-438c-4a0d-a26a-50921e6f01ec@googlegroups.com...
On Wednesday, May 18, 2016 at 4:33:52 AM UTC-4, szczepan bialek
wrote:
https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt, combs, and
rollers invisibly combine to form an electrostatic device called a
Continuously Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle
and flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*

Both? I'm not sure what the question is? Bill Beaty hangs out at
SED, you can
ask him directly.

Wiki and Bill Beaty describe the same device: "The standard
classroom Van de Graff machine contains no power supply."
In the whole world is probably milions such devices. All are the
same. The question is:
Is on the sphere of the standard classroom Van de Graff machine the
excess of electrons or the deficyt?
S*

Could it be either or both. Depending upon charge polarity. If lower
roller is negative then the sphere must be positive and Visa versa.

--
Best Regards:
Baron.

 

[Phil Hobbs]

On 05/18/2016 03:26 PM, Baron wrote:

szczepan bialek prodded the keyboard with:


"George Herold" <gherold@teachspin.com> napisa� w wiadomo�ci
news:d7387b92-438c-4a0d-a26a-50921e6f01ec@googlegroups.com...
On Wednesday, May 18, 2016 at 4:33:52 AM UTC-4, szczepan bialek
wrote:
https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt, combs, and
rollers invisibly combine to form an electrostatic device called a
Continuously Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle
and flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*

Both? I'm not sure what the question is? Bill Beaty hangs out at
SED, you can
ask him directly.

Wiki and Bill Beaty describe the same device: "The standard
classroom Van de Graff machine contains no power supply."
In the whole world is probably milions such devices. All are the
same. The question is:
Is on the sphere of the standard classroom Van de Graff machine the
excess of electrons or the deficyt?
S*

Could it be either or both. Depending upon charge polarity. If lower
roller is negative then the sphere must be positive and Visa versa.

The charge generation process is triboelectric. If you peel an
initially uncharged piece of rubber off a metal surface, it acquires a
charge that depends on its composition. Rubbers can be positive or
negative--see e.g.

https://www.trifield.com/content/tribo-electric-series/

Column 3 of the table is the polarity and strength of the charge
acquired when rubbed against metal.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

 

[George Herold]

On Wednesday, May 18, 2016 at 10:47:59 AM UTC-4, szczepan bialek wrote:

"George Herold" <gherold@teachspin.com> napisał w wiadomości
news:d7387b92-438c-4a0d-a26a-50921e6f01ec@googlegroups.com...
On Wednesday, May 18, 2016 at 4:33:52 AM UTC-4, szczepan bialek wrote:
https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt, combs, and rollers
invisibly combine to form an electrostatic device called a Continuously
Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle and
flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*

Both? I'm not sure what the question is? Bill Beaty hangs out at SED,
you can
ask him directly.

Wiki and Bill Beaty describe the same device: "The standard classroom Van de
Graff machine contains no power supply."
In the whole world is probably milions such devices. All are the same.
The question is:
Is on the sphere of the standard classroom Van de Graff machine the excess
of electrons or the deficyt?
S*

Do you have one in front of you? You could try and measure the sign of the
voltage.. maybe run it very slowly... just a little.. so that it doesn't get
too high? (use a cheap DMM so if it does fry it you won't be out much.)

George H.

 

[szczepan bialek]

"Phil Hobbs" <pcdhSpamMeSenseless@electrooptical.net> napisał w wiadomości
news:_eWdnQv3c6iOV6HKnZ2dnUU7-LvNnZ2d@supernews.com...

On 05/18/2016 03:26 PM, Baron wrote:
szczepan bialek prodded the keyboard with:


"George Herold" <gherold@teachspin.com> napisa? w wiadomo?ci
news:d7387b92-438c-4a0d-a26a-50921e6f01ec@googlegroups.com...
On Wednesday, May 18, 2016 at 4:33:52 AM UTC-4, szczepan bialek
wrote:
https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt, combs, and
rollers invisibly combine to form an electrostatic device called a
Continuously Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle
and flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*

Both? I'm not sure what the question is? Bill Beaty hangs out at
SED, you can
ask him directly.

Wiki and Bill Beaty describe the same device: "The standard
classroom Van de Graff machine contains no power supply."
In the whole world is probably milions such devices. All are the
same. The question is:
Is on the sphere of the standard classroom Van de Graff machine the
excess of electrons or the deficyt?
S*

Could it be either or both. Depending upon charge polarity. If lower
roller is negative then the sphere must be positive and Visa versa.


The charge generation process is triboelectric. If you peel an
initially uncharged piece of rubber off a metal surface, it acquires a
charge that depends on its composition. Rubbers can be positive or
negative--see e.g.

https://www.trifield.com/content/tribo-electric-series/

Column 3 of the table is the polarity and strength of the charge
acquired when rubbed against metal.

But the question was: "Is on the sphere of the standard classroom Van de
Graff machine the
excess of electrons or the deficyt?

In the oryginal was the "+" and "-":
http://todayinsci.com/Events/Patent/VanDeGraaffGenerator1991236-01.htm
S*

 

[Phil Hobbs]

On 05/19/2016 05:10 AM, szczepan bialek wrote:

"Phil Hobbs" <pcdhSpamMeSenseless@electrooptical.net> napisał w wiadomości
news:_eWdnQv3c6iOV6HKnZ2dnUU7-LvNnZ2d@supernews.com...
On 05/18/2016 03:26 PM, Baron wrote:
szczepan bialek prodded the keyboard with:


"George Herold" <gherold@teachspin.com> napisa? w wiadomo?ci
news:d7387b92-438c-4a0d-a26a-50921e6f01ec@googlegroups.com...
On Wednesday, May 18, 2016 at 4:33:52 AM UTC-4, szczepan bialek
wrote:
https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt, combs, and
rollers invisibly combine to form an electrostatic device called a
Continuously Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle
and flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*

Both? I'm not sure what the question is? Bill Beaty hangs out at
SED, you can
ask him directly.

Wiki and Bill Beaty describe the same device: "The standard
classroom Van de Graff machine contains no power supply."
In the whole world is probably milions such devices. All are the
same. The question is:
Is on the sphere of the standard classroom Van de Graff machine the
excess of electrons or the deficyt?
S*

Could it be either or both. Depending upon charge polarity. If lower
roller is negative then the sphere must be positive and Visa versa.


The charge generation process is triboelectric. If you peel an
initially uncharged piece of rubber off a metal surface, it acquires a
charge that depends on its composition. Rubbers can be positive or
negative--see e.g.

https://www.trifield.com/content/tribo-electric-series/

Column 3 of the table is the polarity and strength of the charge
acquired when rubbed against metal.

But the question was: "Is on the sphere of the standard classroom Van de
Graff machine the
excess of electrons or the deficyt?

In the oryginal was the "+" and "-":
http://todayinsci.com/Events/Patent/VanDeGraaffGenerator1991236-01.htm
S*

Which I answered, if you look at the table in the referenced page.
Different kinds of rubber have positive and negative charging against
metal. What kind of rubber does a "standard classroom van de Graaf"
use? Are they all the same?

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

 

[Tom Biasi]

On 5/19/2016 10:18 AM, Phil Hobbs wrote:

On 05/19/2016 05:10 AM, szczepan bialek wrote:
"Phil Hobbs" <pcdhSpamMeSenseless@electrooptical.net> napisał w wiadomości
news:_eWdnQv3c6iOV6HKnZ2dnUU7-LvNnZ2d@supernews.com...
On 05/18/2016 03:26 PM, Baron wrote:
szczepan bialek prodded the keyboard with:


"George Herold" <gherold@teachspin.com> napisa? w wiadomo?ci
news:d7387b92-438c-4a0d-a26a-50921e6f01ec@googlegroups.com...
On Wednesday, May 18, 2016 at 4:33:52 AM UTC-4, szczepan bialek
wrote:
https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt, combs, and
rollers invisibly combine to form an electrostatic device called a
Continuously Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle
and flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*

Both? I'm not sure what the question is? Bill Beaty hangs out at
SED, you can
ask him directly.

Wiki and Bill Beaty describe the same device: "The standard
classroom Van de Graff machine contains no power supply."
In the whole world is probably milions such devices. All are the
same. The question is:
Is on the sphere of the standard classroom Van de Graff machine the
excess of electrons or the deficyt?
S*

Could it be either or both. Depending upon charge polarity. If lower
roller is negative then the sphere must be positive and Visa versa.


The charge generation process is triboelectric. If you peel an
initially uncharged piece of rubber off a metal surface, it acquires a
charge that depends on its composition. Rubbers can be positive or
negative--see e.g.

https://www.trifield.com/content/tribo-electric-series/

Column 3 of the table is the polarity and strength of the charge
acquired when rubbed against metal.

But the question was: "Is on the sphere of the standard classroom Van de
Graff machine the
excess of electrons or the deficyt?

In the oryginal was the "+" and "-":
http://todayinsci.com/Events/Patent/VanDeGraaffGenerator1991236-01.htm
S*

Which I answered, if you look at the table in the referenced page.
Different kinds of rubber have positive and negative charging against
metal. What kind of rubber does a "standard classroom van de Graaf"
use? Are they all the same?

Cheers

Phil Hobbs

If it's a "Van de Graaf" shouldn't it follow Dr, Van de Graaf's design?

 

[Baron]

Phil Hobbs prodded the keyboard with:

On 05/18/2016 03:26 PM, Baron wrote:
szczepan bialek prodded the keyboard with:


"George Herold" <gherold@teachspin.com> napisa� w wiadomo�ci
news:d7387b92-438c-4a0d-a26a-50921e6f01ec@googlegroups.com...
On Wednesday, May 18, 2016 at 4:33:52 AM UTC-4, szczepan bialek
wrote:
https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt, combs,
and rollers invisibly combine to form an electrostatic device
called a Continuously Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the negative surface charge on the belt
has "leapt" onto the needle and flowed to the surface of the
Van de Graaff sphere."

So who is right?
S*

Both? I'm not sure what the question is? Bill Beaty hangs out
at SED, you can
ask him directly.

Wiki and Bill Beaty describe the same device: "The standard
classroom Van de Graff machine contains no power supply."
In the whole world is probably milions such devices. All are the
same. The question is:
Is on the sphere of the standard classroom Van de Graff machine
the excess of electrons or the deficyt?
S*

Could it be either or both. Depending upon charge polarity. If
lower roller is negative then the sphere must be positive and Visa
versa.


The charge generation process is triboelectric. If you peel an
initially uncharged piece of rubber off a metal surface, it acquires
a charge that depends on its composition. Rubbers can be positive
or negative--see e.g.

https://www.trifield.com/content/tribo-electric-series/

Column 3 of the table is the polarity and strength of the charge
acquired when rubbed against metal.

Cheers

Phil Hobbs

Thanks for the informative link.

--
Best Regards:
Baron.

 

[Phil Hobbs]

On 05/19/2016 10:24 AM, Tom Biasi wrote:

On 5/19/2016 10:18 AM, Phil Hobbs wrote:
On 05/19/2016 05:10 AM, szczepan bialek wrote:
"Phil Hobbs" <pcdhSpamMeSenseless@electrooptical.net> napisał w
wiadomości
news:_eWdnQv3c6iOV6HKnZ2dnUU7-LvNnZ2d@supernews.com...
On 05/18/2016 03:26 PM, Baron wrote:
szczepan bialek prodded the keyboard with:


"George Herold" <gherold@teachspin.com> napisa? w wiadomo?ci
news:d7387b92-438c-4a0d-a26a-50921e6f01ec@googlegroups.com...
On Wednesday, May 18, 2016 at 4:33:52 AM UTC-4, szczepan bialek
wrote:
https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt, combs, and
rollers invisibly combine to form an electrostatic device called a
Continuously Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle
and flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*

Both? I'm not sure what the question is? Bill Beaty hangs out at
SED, you can
ask him directly.

Wiki and Bill Beaty describe the same device: "The standard
classroom Van de Graff machine contains no power supply."
In the whole world is probably milions such devices. All are the
same. The question is:
Is on the sphere of the standard classroom Van de Graff machine the
excess of electrons or the deficyt?
S*

Could it be either or both. Depending upon charge polarity. If lower
roller is negative then the sphere must be positive and Visa versa.


The charge generation process is triboelectric. If you peel an
initially uncharged piece of rubber off a metal surface, it acquires a
charge that depends on its composition. Rubbers can be positive or
negative--see e.g.

https://www.trifield.com/content/tribo-electric-series/

Column 3 of the table is the polarity and strength of the charge
acquired when rubbed against metal.

But the question was: "Is on the sphere of the standard classroom Van de
Graff machine the
excess of electrons or the deficyt?

In the oryginal was the "+" and "-":
http://todayinsci.com/Events/Patent/VanDeGraaffGenerator1991236-01.htm
S*

Which I answered, if you look at the table in the referenced page.
Different kinds of rubber have positive and negative charging against
metal. What kind of rubber does a "standard classroom van de Graaf"
use? Are they all the same?

Cheers

Phil Hobbs

If it's a "Van de Graaf" shouldn't it follow Dr, Van de Graaf's design?

All your designs use CK722s and uA709s then?

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

 

[Tom Biasi]

On 5/19/2016 10:38 AM, Phil Hobbs wrote:

On 05/19/2016 10:24 AM, Tom Biasi wrote:
On 5/19/2016 10:18 AM, Phil Hobbs wrote:
On 05/19/2016 05:10 AM, szczepan bialek wrote:
"Phil Hobbs" <pcdhSpamMeSenseless@electrooptical.net> napisał w
wiadomości
news:_eWdnQv3c6iOV6HKnZ2dnUU7-LvNnZ2d@supernews.com...
On 05/18/2016 03:26 PM, Baron wrote:
szczepan bialek prodded the keyboard with:


"George Herold" <gherold@teachspin.com> napisa? w wiadomo?ci
news:d7387b92-438c-4a0d-a26a-50921e6f01ec@googlegroups.com...
On Wednesday, May 18, 2016 at 4:33:52 AM UTC-4, szczepan bialek
wrote:
https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt, combs, and
rollers invisibly combine to form an electrostatic device called a
Continuously Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle
and flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*

Both? I'm not sure what the question is? Bill Beaty hangs out at
SED, you can
ask him directly.

Wiki and Bill Beaty describe the same device: "The standard
classroom Van de Graff machine contains no power supply."
In the whole world is probably milions such devices. All are the
same. The question is:
Is on the sphere of the standard classroom Van de Graff machine the
excess of electrons or the deficyt?
S*

Could it be either or both. Depending upon charge polarity. If lower
roller is negative then the sphere must be positive and Visa versa.


The charge generation process is triboelectric. If you peel an
initially uncharged piece of rubber off a metal surface, it acquires a
charge that depends on its composition. Rubbers can be positive or
negative--see e.g.

https://www.trifield.com/content/tribo-electric-series/

Column 3 of the table is the polarity and strength of the charge
acquired when rubbed against metal.

But the question was: "Is on the sphere of the standard classroom Van de
Graff machine the
excess of electrons or the deficyt?

In the oryginal was the "+" and "-":
http://todayinsci.com/Events/Patent/VanDeGraaffGenerator1991236-01.htm
S*

Which I answered, if you look at the table in the referenced page.
Different kinds of rubber have positive and negative charging against
metal. What kind of rubber does a "standard classroom van de Graaf"
use? Are they all the same?

Cheers

Phil Hobbs

If it's a "Van de Graaf" shouldn't it follow Dr, Van de Graaf's design?

All your designs use CK722s and uA709s then?

Cheers

Phil Hobbs

Classroom Van de Graaf generators were made for teaching the principle
concepts put forth by Dr. Van de Graaf. It would be nice if the model
represented that.

 

[Phil Hobbs]

On 05/19/2016 12:45 PM, Tom Biasi wrote:

On 5/19/2016 10:38 AM, Phil Hobbs wrote:
On 05/19/2016 10:24 AM, Tom Biasi wrote:
On 5/19/2016 10:18 AM, Phil Hobbs wrote:
On 05/19/2016 05:10 AM, szczepan bialek wrote:
"Phil Hobbs" <pcdhSpamMeSenseless@electrooptical.net> napisał w
wiadomości
news:_eWdnQv3c6iOV6HKnZ2dnUU7-LvNnZ2d@supernews.com...
On 05/18/2016 03:26 PM, Baron wrote:
szczepan bialek prodded the keyboard with:


"George Herold" <gherold@teachspin.com> napisa? w wiadomo?ci
news:d7387b92-438c-4a0d-a26a-50921e6f01ec@googlegroups.com...
On Wednesday, May 18, 2016 at 4:33:52 AM UTC-4, szczepan bialek
wrote:
https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt, combs, and
rollers invisibly combine to form an electrostatic device
called a
Continuously Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle
and flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*

Both? I'm not sure what the question is? Bill Beaty hangs out at
SED, you can
ask him directly.

Wiki and Bill Beaty describe the same device: "The standard
classroom Van de Graff machine contains no power supply."
In the whole world is probably milions such devices. All are the
same. The question is:
Is on the sphere of the standard classroom Van de Graff machine the
excess of electrons or the deficyt?
S*

Could it be either or both. Depending upon charge polarity. If
lower
roller is negative then the sphere must be positive and Visa versa.


The charge generation process is triboelectric. If you peel an
initially uncharged piece of rubber off a metal surface, it
acquires a
charge that depends on its composition. Rubbers can be positive or
negative--see e.g.

https://www.trifield.com/content/tribo-electric-series/

Column 3 of the table is the polarity and strength of the charge
acquired when rubbed against metal.

But the question was: "Is on the sphere of the standard classroom
Van de
Graff machine the
excess of electrons or the deficyt?

In the oryginal was the "+" and "-":
http://todayinsci.com/Events/Patent/VanDeGraaffGenerator1991236-01.htm

S*

Which I answered, if you look at the table in the referenced page.
Different kinds of rubber have positive and negative charging against
metal. What kind of rubber does a "standard classroom van de Graaf"
use? Are they all the same?

Cheers

Phil Hobbs

If it's a "Van de Graaf" shouldn't it follow Dr, Van de Graaf's design?

All your designs use CK722s and uA709s then?

Cheers

Phil Hobbs

Classroom Van de Graaf generators were made for teaching the principle
concepts put forth by Dr. Van de Graaf. It would be nice if the model
represented that.

Why? It generates HV triboelectrically, which is the point of the demo.
I think it's cool that by changing a belt you can have positive and
negative HV.

For instance, positive and negative corona discharges look and act very
differently.

Wiki says that his first one used a silk thread, which assuming it's
electrically like human hair, should charge up positive.

Assuming that his second one used latex rubber, which is probably a good
guess for 1929, that would charge negative. Which is the real authentic
van de Graaf in your view?

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

 

[Tom Biasi]

On 5/19/2016 3:14 PM, Phil Hobbs wrote:

On 05/19/2016 12:45 PM, Tom Biasi wrote:
On 5/19/2016 10:38 AM, Phil Hobbs wrote:
On 05/19/2016 10:24 AM, Tom Biasi wrote:
On 5/19/2016 10:18 AM, Phil Hobbs wrote:
On 05/19/2016 05:10 AM, szczepan bialek wrote:
"Phil Hobbs" <pcdhSpamMeSenseless@electrooptical.net> napisał w
wiadomości
news:_eWdnQv3c6iOV6HKnZ2dnUU7-LvNnZ2d@supernews.com...
On 05/18/2016 03:26 PM, Baron wrote:
szczepan bialek prodded the keyboard with:


"George Herold" <gherold@teachspin.com> napisa? w wiadomo?ci
news:d7387b92-438c-4a0d-a26a-50921e6f01ec@googlegroups.com...
On Wednesday, May 18, 2016 at 4:33:52 AM UTC-4, szczepan bialek
wrote:
https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt, combs, and
rollers invisibly combine to form an electrostatic device
called a
Continuously Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle
and flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*

Both? I'm not sure what the question is? Bill Beaty hangs out at
SED, you can
ask him directly.

Wiki and Bill Beaty describe the same device: "The standard
classroom Van de Graff machine contains no power supply."
In the whole world is probably milions such devices. All are the
same. The question is:
Is on the sphere of the standard classroom Van de Graff machine the
excess of electrons or the deficyt?
S*

Could it be either or both. Depending upon charge polarity. If
lower
roller is negative then the sphere must be positive and Visa versa.


The charge generation process is triboelectric. If you peel an
initially uncharged piece of rubber off a metal surface, it
acquires a
charge that depends on its composition. Rubbers can be positive or
negative--see e.g.

https://www.trifield.com/content/tribo-electric-series/

Column 3 of the table is the polarity and strength of the charge
acquired when rubbed against metal.

But the question was: "Is on the sphere of the standard classroom
Van de
Graff machine the
excess of electrons or the deficyt?

In the oryginal was the "+" and "-":
http://todayinsci.com/Events/Patent/VanDeGraaffGenerator1991236-01.htm

S*

Which I answered, if you look at the table in the referenced page.
Different kinds of rubber have positive and negative charging against
metal. What kind of rubber does a "standard classroom van de Graaf"
use? Are they all the same?

Cheers

Phil Hobbs

If it's a "Van de Graaf" shouldn't it follow Dr, Van de Graaf's design?

All your designs use CK722s and uA709s then?

Cheers

Phil Hobbs

Classroom Van de Graaf generators were made for teaching the principle
concepts put forth by Dr. Van de Graaf. It would be nice if the model
represented that.

Why? It generates HV triboelectrically, which is the point of the demo.
I think it's cool that by changing a belt you can have positive and
negative HV.

For instance, positive and negative corona discharges look and act very
differently.

Wiki says that his first one used a silk thread, which assuming it's
electrically like human hair, should charge up positive.

Assuming that his second one used latex rubber, which is probably a good
guess for 1929, that would charge negative. Which is the real authentic
van de Graaf in your view?

Cheers

Phil Hobbs

If I use his name I like the demo to represent what he did. There are
many ways to generate static electricity but this one is his.
Not a big deal, just me.

 

[Phil Hobbs]

On 05/19/2016 03:52 PM, Tom Biasi wrote:

On 5/19/2016 3:14 PM, Phil Hobbs wrote:
On 05/19/2016 12:45 PM, Tom Biasi wrote:
On 5/19/2016 10:38 AM, Phil Hobbs wrote:
On 05/19/2016 10:24 AM, Tom Biasi wrote:
On 5/19/2016 10:18 AM, Phil Hobbs wrote:
On 05/19/2016 05:10 AM, szczepan bialek wrote:
"Phil Hobbs" <pcdhSpamMeSenseless@electrooptical.net> napisał w
wiadomości
news:_eWdnQv3c6iOV6HKnZ2dnUU7-LvNnZ2d@supernews.com...
On 05/18/2016 03:26 PM, Baron wrote:
szczepan bialek prodded the keyboard with:


"George Herold" <gherold@teachspin.com> napisa? w wiadomo?ci
news:d7387b92-438c-4a0d-a26a-50921e6f01ec@googlegroups.com...
On Wednesday, May 18, 2016 at 4:33:52 AM UTC-4, szczepan bialek
wrote:
https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt,
combs, and
rollers invisibly combine to form an electrostatic device
called a
Continuously Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle
and flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*

Both? I'm not sure what the question is? Bill Beaty hangs
out at
SED, you can
ask him directly.

Wiki and Bill Beaty describe the same device: "The standard
classroom Van de Graff machine contains no power supply."
In the whole world is probably milions such devices. All are the
same. The question is:
Is on the sphere of the standard classroom Van de Graff
machine the
excess of electrons or the deficyt?
S*

Could it be either or both. Depending upon charge polarity. If
lower
roller is negative then the sphere must be positive and Visa
versa.


The charge generation process is triboelectric. If you peel an
initially uncharged piece of rubber off a metal surface, it
acquires a
charge that depends on its composition. Rubbers can be positive or
negative--see e.g.

https://www.trifield.com/content/tribo-electric-series/

Column 3 of the table is the polarity and strength of the charge
acquired when rubbed against metal.

But the question was: "Is on the sphere of the standard classroom
Van de
Graff machine the
excess of electrons or the deficyt?

In the oryginal was the "+" and "-":
http://todayinsci.com/Events/Patent/VanDeGraaffGenerator1991236-01.htm


S*

Which I answered, if you look at the table in the referenced page.
Different kinds of rubber have positive and negative charging against
metal. What kind of rubber does a "standard classroom van de Graaf"
use? Are they all the same?

Cheers

Phil Hobbs

If it's a "Van de Graaf" shouldn't it follow Dr, Van de Graaf's
design?

All your designs use CK722s and uA709s then?

Cheers

Phil Hobbs

Classroom Van de Graaf generators were made for teaching the principle
concepts put forth by Dr. Van de Graaf. It would be nice if the model
represented that.

Why? It generates HV triboelectrically, which is the point of the demo.
I think it's cool that by changing a belt you can have positive and
negative HV.

For instance, positive and negative corona discharges look and act very
differently.

Wiki says that his first one used a silk thread, which assuming it's
electrically like human hair, should charge up positive.

Assuming that his second one used latex rubber, which is probably a good
guess for 1929, that would charge negative. Which is the real authentic
van de Graaf in your view?

Cheers

Phil Hobbs

If I use his name I like the demo to represent what he did. There are
many ways to generate static electricity but this one is his.
Not a big deal, just me.

But he did lots of them.

Cheers

Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

 

[Tom Biasi]

On 5/19/2016 4:22 PM, Phil Hobbs wrote:

On 05/19/2016 03:52 PM, Tom Biasi wrote:
On 5/19/2016 3:14 PM, Phil Hobbs wrote:
On 05/19/2016 12:45 PM, Tom Biasi wrote:
On 5/19/2016 10:38 AM, Phil Hobbs wrote:
On 05/19/2016 10:24 AM, Tom Biasi wrote:
On 5/19/2016 10:18 AM, Phil Hobbs wrote:
On 05/19/2016 05:10 AM, szczepan bialek wrote:
"Phil Hobbs" <pcdhSpamMeSenseless@electrooptical.net> napisał w
wiadomości
news:_eWdnQv3c6iOV6HKnZ2dnUU7-LvNnZ2d@supernews.com...
On 05/18/2016 03:26 PM, Baron wrote:
szczepan bialek prodded the keyboard with:


"George Herold" <gherold@teachspin.com> napisa? w wiadomo?ci
news:d7387b92-438c-4a0d-a26a-50921e6f01ec@googlegroups.com...
On Wednesday, May 18, 2016 at 4:33:52 AM UTC-4, szczepan bialek
wrote:
https://pl.wikipedia.org/wiki/Plik:Van_de_graaf_generator.svg

There are the positive charge on the sphere.

But in the another description we can read:
""Although they look simple at first glance, the belt,
combs, and
rollers invisibly combine to form an electrostatic device
called a
Continuously Operating Electrophorus". From:
http://amasci.com/emotor/belt.html

"On average, the
negative surface charge on the belt has "leapt" onto the needle
and flowed
to the surface of the Van de Graaff sphere."

So who is right?
S*

Both? I'm not sure what the question is? Bill Beaty hangs
out at
SED, you can
ask him directly.

Wiki and Bill Beaty describe the same device: "The standard
classroom Van de Graff machine contains no power supply."
In the whole world is probably milions such devices. All are the
same. The question is:
Is on the sphere of the standard classroom Van de Graff
machine the
excess of electrons or the deficyt?
S*

Could it be either or both. Depending upon charge polarity. If
lower
roller is negative then the sphere must be positive and Visa
versa.


The charge generation process is triboelectric. If you peel an
initially uncharged piece of rubber off a metal surface, it
acquires a
charge that depends on its composition. Rubbers can be positive or
negative--see e.g.

https://www.trifield.com/content/tribo-electric-series/

Column 3 of the table is the polarity and strength of the charge
acquired when rubbed against metal.

But the question was: "Is on the sphere of the standard classroom
Van de
Graff machine the
excess of electrons or the deficyt?

In the oryginal was the "+" and "-":
http://todayinsci.com/Events/Patent/VanDeGraaffGenerator1991236-01.htm


S*

Which I answered, if you look at the table in the referenced page.
Different kinds of rubber have positive and negative charging against
metal. What kind of rubber does a "standard classroom van de Graaf"
use? Are they all the same?

Cheers

Phil Hobbs

If it's a "Van de Graaf" shouldn't it follow Dr, Van de Graaf's
design?

All your designs use CK722s and uA709s then?

Cheers

Phil Hobbs

Classroom Van de Graaf generators were made for teaching the principle
concepts put forth by Dr. Van de Graaf. It would be nice if the model
represented that.

Why? It generates HV triboelectrically, which is the point of the demo.
I think it's cool that by changing a belt you can have positive and
negative HV.

For instance, positive and negative corona discharges look and act very
differently.

Wiki says that his first one used a silk thread, which assuming it's
electrically like human hair, should charge up positive.

Assuming that his second one used latex rubber, which is probably a good
guess for 1929, that would charge negative. Which is the real authentic
van de Graaf in your view?

Cheers

Phil Hobbs

If I use his name I like the demo to represent what he did. There are
many ways to generate static electricity but this one is his.
Not a big deal, just me.

But he did lots of them.

Cheers

Phil Hobbs

OK

 

[szczepan bialek]

"George Herold" <gherold@teachspin.com> napisał w wiadomości
news:ff6e257f-ed4d-419f-857a-4a898e69be45@googlegroups.com...
On Wednesday, May 18, 2016 at 10:47:59 AM UTC-4, szczepan bialek wrote:

Wiki and Bill Beaty describe the same device: "The standard classroom Van
de
Graff machine contains no power supply."
In the whole world is probably milions such devices. All are the same.
The question is:
Is on the sphere of the standard classroom Van de Graff machine the excess
of electrons or the deficyt?
S*

"Do you have one in front of you? You could try and measure the sign of the
voltage.. maybe run it very slowly... just a little.. so that it doesn't get
too high? (use a cheap DMM so if it does fry it you won't be out much.)

George H."

<Of course not.
<My question is directed to that who have one in front of his eays.
S*