Understanding voltage

[bgold12]

Hey, I'm in 3rd year mechanical engineering and I still don't feel
like I have a strong understanding of what voltage is. Maybe someone
can help explain the concept.

I'm pretty sure I understand what charge is (it's just a fundamental
property of subatomic particles that affect the way they interact,
i.e. a charged particle induces a force on a surrounding charged
particle based on their charges (+e for a proton, -e for an electron,
and 0 for a neutron) and the distance and properties of the volume
between them), and I'm pretty sure I understand current, which is just
moving charges (I picture a bunch of electrons moving through a volume
between idle nuclei). But I don't get the concept of voltage. I know
it's produced from a separation of charges, and it is energy per
charge, or Joules/Coulomb, but where is the energy contained? How does
the coulomb of charged particles "have" this energy, and how is it
possible that there can be different amounts of energy associated with
a fixed amount of charged particles (i.e. you can have 10 joules/2
coulombs = 5 volts, but you can also have 20 joules/2 coulombs = 10
volts?)?

I hope that was clear, but it probably wasn't.

Thanks,

bgold12

 

[Tim Wescott]

bgold12 wrote:

Hey, I'm in 3rd year mechanical engineering and I still don't feel
like I have a strong understanding of what voltage is. Maybe someone
can help explain the concept.

I'm pretty sure I understand what charge is (it's just a fundamental
property of subatomic particles that affect the way they interact,
i.e. a charged particle induces a force on a surrounding charged
particle based on their charges (+e for a proton, -e for an electron,
and 0 for a neutron) and the distance and properties of the volume
between them), and I'm pretty sure I understand current, which is just
moving charges (I picture a bunch of electrons moving through a volume
between idle nuclei). But I don't get the concept of voltage. I know
it's produced from a separation of charges, and it is energy per
charge, or Joules/Coulomb, but where is the energy contained? How does
the coulomb of charged particles "have" this energy, and how is it
possible that there can be different amounts of energy associated with
a fixed amount of charged particles (i.e. you can have 10 joules/2
coulombs = 5 volts, but you can also have 20 joules/2 coulombs = 10
volts?)?

I hope that was clear, but it probably wasn't.

Thanks,

bgold12

This easily yields to experiment. Try this:

Grab one coulomb of positive charge in one hand, and one coulomb of
negative charge in the other. Now draw your hands apart until they are
separated by 1 meter. You'll note that the force trying to draw your
hands together is about 9e9 Newtons (it helps to do this test in a
universe where you are many times stronger than here, and where you can
hold point charges in your hands -- there may be one in your Physics
building, check with a prof).

Now as you drew your hands apart, you will have noted that you had to
exert force to do so, and this force was exerted over some distance --
i.e. you performed work on the charges. Solving for energy = work *
distance, you conclude that you have added energy to the charges.

HTH.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" gives you just what it says.
See details at http://www.wescottdesign.com/actfes/actfes.html

 

[Tim Wescott]

Rose wrote:

On Sep 29, 9:59 am, bgold12 <bgol...@gmail.com> wrote:
Hey, I'm in 3rd year mechanical engineering and I still don't feel
like I have a strong understanding of what voltage is. Maybe someone
can help explain the concept.

I'm pretty sure I understand what charge is (it's just a fundamental
property of subatomic particles that affect the way they interact,
i.e. a charged particle induces a force on a surrounding charged
particle based on their charges (+e for a proton, -e for an electron,
and 0 for a neutron) and the distance and properties of the volume
between them), and I'm pretty sure I understand current, which is just
moving charges (I picture a bunch of electrons moving through a volume
between idle nuclei). But I don't get the concept of voltage. I know
it's produced from a separation of charges, and it is energy per
charge, or Joules/Coulomb, but where is the energy contained? How does
the coulomb of charged particles "have" this energy, and how is it
possible that there can be different amounts of energy associated with
a fixed amount of charged particles (i.e. you can have 10 joules/2
coulombs = 5 volts, but you can also have 20 joules/2 coulombs = 10
volts?)?

I hope that was clear, but it probably wasn't.

Thanks,

bgold12

What I can't understand is how a person can be in third year
engineering and not have a strong understanding of what voltage is.

3rd year _mechanical_ engineering. And he's working to fill in the
gaps, which is more than a lot of mechanical engineering students might do.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" gives you just what it says.
See details at http://www.wescottdesign.com/actfes/actfes.html

 

[Rose]

On Sep 29, 9:59 am, bgold12 <bgol...@gmail.com> wrote:

Hey, I'm in 3rd year mechanical engineering and I still don't feel
like I have a strong understanding of what voltage is. Maybe someone
can help explain the concept.

I'm pretty sure I understand what charge is (it's just a fundamental
property of subatomic particles that affect the way they interact,
i.e. a charged particle induces a force on a surrounding charged
particle based on their charges (+e for a proton, -e for an electron,
and 0 for a neutron) and the distance and properties of the volume
between them), and I'm pretty sure I understand current, which is just
moving charges (I picture a bunch of electrons moving through a volume
between idle nuclei). But I don't get the concept of voltage. I know
it's produced from a separation of charges, and it is energy per
charge, or Joules/Coulomb, but where is the energy contained? How does
the coulomb of charged particles "have" this energy, and how is it
possible that there can be different amounts of energy associated with
a fixed amount of charged particles (i.e. you can have 10 joules/2
coulombs = 5 volts, but you can also have 20 joules/2 coulombs = 10
volts?)?

I hope that was clear, but it probably wasn't.

Thanks,

bgold12

What I can't understand is how a person can be in third year
engineering and not have a strong understanding of what voltage is.

 

[StickThatInYourPipeAndSmo]

On Mon, 29 Sep 2008 11:57:18 -0700 (PDT), Rose <couple7802002@yahoo.com>
wrote:

On Sep 29, 9:59 am, bgold12 <bgol...@gmail.com> wrote:
Hey, I'm in 3rd year mechanical engineering and I still don't feel
like I have a strong understanding of what voltage is. Maybe someone
can help explain the concept.

I'm pretty sure I understand what charge is (it's just a fundamental
property of subatomic particles that affect the way they interact,
i.e. a charged particle induces a force on a surrounding charged
particle based on their charges (+e for a proton, -e for an electron,
and 0 for a neutron) and the distance and properties of the volume
between them), and I'm pretty sure I understand current, which is just
moving charges (I picture a bunch of electrons moving through a volume
between idle nuclei). But I don't get the concept of voltage. I know
it's produced from a separation of charges, and it is energy per
charge, or Joules/Coulomb, but where is the energy contained? How does
the coulomb of charged particles "have" this energy, and how is it
possible that there can be different amounts of energy associated with
a fixed amount of charged particles (i.e. you can have 10 joules/2
coulombs = 5 volts, but you can also have 20 joules/2 coulombs = 10
volts?)?

I hope that was clear, but it probably wasn't.

Thanks,

bgold12

What I can't understand is how a person can be in third year
engineering and not have a strong understanding of what voltage is.

Even worse... they somehow get good grades, and after they get their
degrees, some of them come to work at our place, and they STILL don't
understand it. Then they pay them engineering salaries and let them
design satellite gear!

Working at a high voltage power supply company did allow me to review,
and lock in a lot of basics. That was a good eight year experience in my
life.

Especially the "one-hand-in-the-pocket" rule. :-]

 

[Archimedes' Lever]

On Mon, 29 Sep 2008 14:06:46 -0700 (PDT), Rose <couple7802002@yahoo.com>
wrote:

No wonder our bridges are falling down.

They were fine when they were built.

However, just like our "economy", the "powers that be" decided to get
lax on the quarter century down the line maintenance requisites they
signed on for when they taxed us to build the bridge.

Modern built bridges are just fine too.

Don't be an idiot. You act as if you think the lies Obama is feeding
the country would actually be able to be enacted, much less work.

Any other Obama styled insults you want to spout?

I have to agree, though... a lot of fucking copying, letting others do
your work for you type shit is currently taking place.

I sure am glad that my character and honor will not allow me to
participate in those stupid behaviors.

 

[Rose]

On Sep 29, 1:24 pm, Tim Wescott <t...@seemywebsite.com> wrote:

Rose wrote:
On Sep 29, 9:59 am, bgold12 <bgol...@gmail.com> wrote:
Hey, I'm in 3rd year mechanical engineering and I still don't feel
like I have a strong understanding of what voltage is. Maybe someone
can help explain the concept.

I'm pretty sure I understand what charge is (it's just a fundamental
property of subatomic particles that affect the way they interact,
i.e. a charged particle induces a force on a surrounding charged
particle based on their charges (+e for a proton, -e for an electron,
and 0 for a neutron) and the distance and properties of the volume
between them), and I'm pretty sure I understand current, which is just
moving charges (I picture a bunch of electrons moving through a volume
between idle nuclei). But I don't get the concept of voltage. I know
it's produced from a separation of charges, and it is energy per
charge, or Joules/Coulomb, but where is the energy contained? How does
the coulomb of charged particles "have" this energy, and how is it
possible that there can be different amounts of energy associated with
a fixed amount of charged particles (i.e. you can have 10 joules/2
coulombs = 5 volts, but you can also have 20 joules/2 coulombs = 10
volts?)?

I hope that was clear, but it probably wasn't.

Thanks,

bgold12

What I can't understand is how a person can be in third year
engineering and not have a strong understanding of what voltage is.

3rd year _mechanical_ engineering.  And he's working to fill in the
gaps, which is more than a lot of mechanical engineering students might do.

--

Tim Wescott
Wescott Design Serviceshttp://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" gives you just what it says..
See details athttp://www.wescottdesign.com/actfes/actfes.html

It's a big gap to fill and a strange place to come to fill it.

 

[Rose]

On Sep 29, 2:06 pm, "Jon Slaughter" <Jon_Slaugh...@Hotmail.com> wrote:

"bgold12" <bgol...@gmail.com> wrote in message

news:16bcac37-c91c-4a5e-94e2-82fe21b9420b@m44g2000hsc.googlegroups.com...



Hey, I'm in 3rd year mechanical engineering and I still don't feel
like I have a strong understanding of what voltage is. Maybe someone
can help explain the concept.

I'm pretty sure I understand what charge is (it's just a fundamental
property of subatomic particles that affect the way they interact,
i.e. a charged particle induces a force on a surrounding charged
particle based on their charges (+e for a proton, -e for an electron,
and 0 for a neutron) and the distance and properties of the volume
between them), and I'm pretty sure I understand current, which is just
moving charges (I picture a bunch of electrons moving through a volume
between idle nuclei). But I don't get the concept of voltage. I know
it's produced from a separation of charges, and it is energy per
charge, or Joules/Coulomb, but where is the energy contained? How does
the coulomb of charged particles "have" this energy, and how is it
possible that there can be different amounts of energy associated with
a fixed amount of charged particles (i.e. you can have 10 joules/2
coulombs = 5 volts, but you can also have 20 joules/2 coulombs = 10
volts?)?

I hope that was clear, but it probably wasn't.

Thanks,

bgold12

Note that everything you have learned about gravity can almost be directly
applied to electricity. In fact the governing equations of EM are almost
exactly the same as that of gravity if you could "remove" the polarity
aspect. (but the consequences can be dramatically different)

Electrons have attraction and repulsion while "matter" has only attraction.

What causet he attraction/repulsion? It is a force. Gravity on one hand and
the electrostatic force on the other.

What about potential energy? Same thing holds for charge. If you take two
charges and bring them close together they will have some sort of potential
energy... they will either attract or repell and that potential will be
converted into kinetic energy just as in mechanics.

Now voltage is a measure of that attraction.

How do you know something has potential energy? You have to let act out on
it. (there is no other way except through analysis but that came about from
observation.

Voltage, or the electric potential(vs the mechanical potential) is a really
a difference in potential energy.

So suppose we have +Q C at (-1, 0) and -Q C at (1, 0), they will attract
each other and have forces on them. this would be simiar case to M kg and M
kg but the magnitudes of hte forces would be different.

This attraction gives rise to a potential and the potential difference is
precisely the voltage. (in the right units for charge)

People tend to speak of voltage as if it were a force(such as electromotive
force which has the same units as voltage) but it is not a force just as
mechanical potential isn't a force... but it can be used to create a force.

You hopefully know that the gravitational force can have an associated
potential with it(the mechanical potential). The same is done with the
electric force. Since the forces are conservative we know by mathematics
that there is a scalar field who's gradient is the force. It's much easier
to work with a scalar field and it's called the potential.

In any case thats more theoretical.

What does it mean in practice?

If someone says that they have a capacitor with 10V "across" it what do they
mean?  It means they can do some work... and if they were smart they could
compute just how much work. All you need ot know is that if there is a
potential difference between two points, any two points, and you stick a
wire at those two points(a conductor) then current will flow. If you have a
lightbulb or led in series with that wire then it might light up... or you
might be able to turn a wire.

The mere fact that there is a potential difference implies that you can do
work and vice versa. (they are identical concepts as force but viewed from a
different perspective)

It doesn't tell you have much work you can do and infact you might not be
able to do any depending on the circumstances... but at least in theory you
can do some work.

It also is related to current... because current flowing means there is a
potential difference. (but not vice versa)

Analogy: A book on a table. The table is a resistance to the book "flowing"
down to the ground.  The book has potential due only to it's position w..r.t
to the earth. If you remove the table the book will convert the
potential(voltage) into kinetic energy(think of current) and when it hits
the ground or something inbetween it would apply a force that can continue
to do work on other things.

There is nothing special about voltage... it's just what we call the
potential for electricity. If you understand the gravitational potential
then you shouldn't have any problem if you just realize that the basic
quanitities one is dealing with are analogous. current = mass flow, voltage
= mechanical potential, force = force, electric field = gravitational field,
etc..

What's more important is that you have some concept of magnitude of
voltage... what is 10V? what is 1000V?  Also helps to know something about
current and what is 1A vs 100A, etc...

By having that kinda knowledge you'll have a better working understanding..
It's similar to mass and energy.  Everyone knows what 100lbs is about.... or
maybe even 1000lbs but most people don't know much about energy. Most people
have a better concept of power than energy as they know their lightbulb is
using maybe 100W. They still don't really have any clue what it means but
they do know it is doing something(i.e. work).

And that's all this boils down too... voltage is a measure of work! Work is
what is important! mass is useless if it can't do any work! current is
useless if it can't do any work!! Current is a measure of charge in
motion... which is usefull to determine how much work it can do.

So ultimately in all the things we are trying to do is to simply things to
determine how much work something can do... by knowing that we know how much
less work we have to do. But of course we can't always measure work
directly... we don't have a special machine that we can ask how much work x
is doing and it tells us. We have to break the problem down and learn how to
measure it which involves measuring bits and pieces.

(I don't mean to sound dramatic about it but the fundamentals of physics is
concerned with it)

Nice job. Now he can go into fourth year.
No wonder our bridges are falling down.

 

[Paul Hovnanian P.E.]

If you tell me where the potential energy goes when I lift a weight up
in a gravitational field, I'll tell you where the energy goes when you
separate two charges.

--
Paul Hovnanian mailtoaul@Hovnanian.com
------------------------------------------------------------------
Your mouse has moved. Windows must be restarted for
the change to take effect. Reboot now? [OK]

 

[John Fields]

On Mon, 29 Sep 2008 11:57:18 -0700 (PDT), Rose <couple7802002@yahoo.com>
wrote:

On Sep 29, 9:59 am, bgold12 <bgol...@gmail.com> wrote:
Hey, I'm in 3rd year mechanical engineering and I still don't feel
like I have a strong understanding of what voltage is. Maybe someone
can help explain the concept.

I'm pretty sure I understand what charge is (it's just a fundamental
property of subatomic particles that affect the way they interact,
i.e. a charged particle induces a force on a surrounding charged
particle based on their charges (+e for a proton, -e for an electron,
and 0 for a neutron) and the distance and properties of the volume
between them), and I'm pretty sure I understand current, which is just
moving charges (I picture a bunch of electrons moving through a volume
between idle nuclei). But I don't get the concept of voltage. I know
it's produced from a separation of charges, and it is energy per
charge, or Joules/Coulomb, but where is the energy contained? How does
the coulomb of charged particles "have" this energy, and how is it
possible that there can be different amounts of energy associated with
a fixed amount of charged particles (i.e. you can have 10 joules/2
coulombs = 5 volts, but you can also have 20 joules/2 coulombs = 10
volts?)?

I hope that was clear, but it probably wasn't.

Thanks,

bgold12

What I can't understand is how a person can be in third year
engineering and not have a strong understanding of what voltage is.

---
Do you also "can't understand" why he may not have a strong
understanding of what a "parsec" is, or a "millihelen", or a zillion
other terms which aren't relevant to his discipline?

Instead of offering him help, as others have done, why do you ridicule
him for seeking knowledge when you should be commending him for the
courage he mustered in exposing his ignorance and asking for help before
the likes of you?

Perhaps because you have no help to give and are intent on pulling your
betters down in order to make your position on the food chain seem
higher than it actually is?

Some roses by any other name would smell as foul.

JF

 

[John Larkin]

On Mon, 29 Sep 2008 11:57:18 -0700 (PDT), Rose
<couple7802002@yahoo.com> wrote:

On Sep 29, 9:59 am, bgold12 <bgol...@gmail.com> wrote:
Hey, I'm in 3rd year mechanical engineering and I still don't feel
like I have a strong understanding of what voltage is. Maybe someone
can help explain the concept.

I'm pretty sure I understand what charge is (it's just a fundamental
property of subatomic particles that affect the way they interact,
i.e. a charged particle induces a force on a surrounding charged
particle based on their charges (+e for a proton, -e for an electron,
and 0 for a neutron) and the distance and properties of the volume
between them), and I'm pretty sure I understand current, which is just
moving charges (I picture a bunch of electrons moving through a volume
between idle nuclei). But I don't get the concept of voltage. I know
it's produced from a separation of charges, and it is energy per
charge, or Joules/Coulomb, but where is the energy contained? How does
the coulomb of charged particles "have" this energy, and how is it
possible that there can be different amounts of energy associated with
a fixed amount of charged particles (i.e. you can have 10 joules/2
coulombs = 5 volts, but you can also have 20 joules/2 coulombs = 10
volts?)?

I hope that was clear, but it probably wasn't.

Thanks,

bgold12

What I can't understand is how a person can be in third year
engineering and not have a strong understanding of what voltage is.

Because it's mechanical engineering?

John

 

[John Fields]

On Mon, 29 Sep 2008 17:36:14 -0700 (PDT), Rose <couple7802002@yahoo.com>
wrote:

On Sep 29, 6:21 pm, John Fields <jfie...@austininstruments.com> wrote:
On Mon, 29 Sep 2008 11:57:18 -0700 (PDT), Rose <couple7802...@yahoo.com
wrote:



On Sep 29, 9:59 am, bgold12 <bgol...@gmail.com> wrote:
Hey, I'm in 3rd year mechanical engineering and I still don't feel
like I have a strong understanding of what voltage is. Maybe someone
can help explain the concept.

I'm pretty sure I understand what charge is (it's just a fundamental
property of subatomic particles that affect the way they interact,
i.e. a charged particle induces a force on a surrounding charged
particle based on their charges (+e for a proton, -e for an electron,
and 0 for a neutron) and the distance and properties of the volume
between them), and I'm pretty sure I understand current, which is just
moving charges (I picture a bunch of electrons moving through a volume
between idle nuclei). But I don't get the concept of voltage. I know
it's produced from a separation of charges, and it is energy per
charge, or Joules/Coulomb, but where is the energy contained? How does
the coulomb of charged particles "have" this energy, and how is it
possible that there can be different amounts of energy associated with
a fixed amount of charged particles (i.e. you can have 10 joules/2
coulombs = 5 volts, but you can also have 20 joules/2 coulombs = 10
volts?)?

I hope that was clear, but it probably wasn't.

Thanks,

bgold12

What I can't understand is how a person can be in third year
engineering and not have a strong understanding of what voltage is.

---
Do you also "can't understand" why he may not have a strong
understanding of what a "parsec" is, or a "millihelen", or a zillion
other terms which aren't relevant to his discipline?

Instead of offering him help, as others have done, why do you ridicule
him for seeking knowledge when you should be commending him for the
courage he mustered in exposing his ignorance and asking for help before
the likes of you?

Perhaps because you have no help to give and are intent on pulling your
betters down in order to make your position on the food chain seem
higher than it actually is?

Some roses by any other name would smell as foul.

JF

At least I wasn't being cranky.

---
Please...

You were being much worse than cranky, you were being intentionally
disingenuous.

JF

 

[Rose]

On Sep 29, 6:21 pm, John Fields <jfie...@austininstruments.com> wrote:

On Mon, 29 Sep 2008 11:57:18 -0700 (PDT), Rose <couple7802...@yahoo.com
wrote:



On Sep 29, 9:59 am, bgold12 <bgol...@gmail.com> wrote:
Hey, I'm in 3rd year mechanical engineering and I still don't feel
like I have a strong understanding of what voltage is. Maybe someone
can help explain the concept.

I'm pretty sure I understand what charge is (it's just a fundamental
property of subatomic particles that affect the way they interact,
i.e. a charged particle induces a force on a surrounding charged
particle based on their charges (+e for a proton, -e for an electron,
and 0 for a neutron) and the distance and properties of the volume
between them), and I'm pretty sure I understand current, which is just
moving charges (I picture a bunch of electrons moving through a volume
between idle nuclei). But I don't get the concept of voltage. I know
it's produced from a separation of charges, and it is energy per
charge, or Joules/Coulomb, but where is the energy contained? How does
the coulomb of charged particles "have" this energy, and how is it
possible that there can be different amounts of energy associated with
a fixed amount of charged particles (i.e. you can have 10 joules/2
coulombs = 5 volts, but you can also have 20 joules/2 coulombs = 10
volts?)?

I hope that was clear, but it probably wasn't.

Thanks,

bgold12

What I can't understand is how a person can be in third year
engineering and not have a strong understanding of what voltage is.

---
Do you also "can't understand" why he may not have a strong
understanding of what a "parsec" is, or a "millihelen", or a zillion
other terms which aren't relevant to his discipline?

Instead of offering him help, as others have done, why do you ridicule
him for seeking knowledge when you should be commending him for the
courage he mustered in exposing his ignorance and asking for help before
the likes of you?

Perhaps because you have no help to give and are intent on pulling your
betters down in order to make your position on the food chain seem
higher than it actually is?

Some roses by any other name would smell as foul.

JF

At least I wasn't being cranky.

 

[Gerald Newton]

On Sep 29, 7:59 am, bgold12 <bgol...@gmail.com> wrote:

Hey, I'm in 3rd year mechanical engineering and I still don't feel
like I have a strong understanding of what voltage is. Maybe someone
can help explain the concept.

I'm pretty sure I understand what charge is (it's just a fundamental
property of subatomic particles that affect the way they interact,
i.e. a charged particle induces a force on a surrounding charged
particle based on their charges (+e for a proton, -e for an electron,
and 0 for a neutron) and the distance and properties of the volume
between them), and I'm pretty sure I understand current, which is just
moving charges (I picture a bunch of electrons moving through a volume
between idle nuclei). But I don't get the concept of voltage. I know
it's produced from a separation of charges, and it is energy per
charge, or Joules/Coulomb, but where is the energy contained? How does
the coulomb of charged particles "have" this energy, and how is it
possible that there can be different amounts of energy associated with
a fixed amount of charged particles (i.e. you can have 10 joules/2
coulombs = 5 volts, but you can also have 20 joules/2 coulombs = 10
volts?)?

I hope that was clear, but it probably wasn't.

Thanks,

bgold12

It might bring some comfort to you to know that the equation to find
the amperes that a conductor can safely carry without overheating
comes from Mechanical Engineering.
It is the Fourier heat transfer equation. Mechanical engineers know a
whole lot more about this than electrical engineers.
The equation is (TC - TA) = I**2 R (RCA)
Solving I = SRT((TC-TA)/(R*RCA))
I in amperes, TC is maximum conductor insulation temperature in
degrees C, TA is ambient temperature in degrees C, R is dc resistance
in ohms of conductor, RCA is thermal Resistance in thermal ohm feet.
I square R is the heat generated in the conductor when I amperes flows
through the conductor with resistance R in ohms. The amperes flow
because of a potential difference in voltage that exist between
conductors.
Variations of this equation were used by Rosch in 1938 and by Msgs
Neher and McGrath in 1957 to develop ampacity tables found in the
National Electrical Code.
This does not tell you what voltage is but it does put some rather
elite electrical engineers that like to poke fun at mechanical
engineers in their place.

 

[krw]

In article <gkhEk.2759$be.1230@nlpi061.nbdc.sbc.com>,
Jon_Slaughter@Hotmail.com says...

...
Nice job. Now he can go into fourth year.
No wonder our bridges are falling down.

When did one have to understand electricity to understand how to build a
bridge?

Mechanical engineers don't build bridges either. They do build
automobiles and robots, though. Basic electricity would seem to be
a useful thing for MEs. Basic physics is rather useful, and
required, for EEs. MEs don't have to take the EM semester of
physics?

I'd rather the guy know squat about electricity and be a great bridge
builder than build shitty ass bridges cause he spent to much time trying to
learn about electricity for some school requirements to "broaden his
horizons". He could have spent that time more wisely.

Try a civil engineer if you want a bridge built. I'd rather my
civil engineer had the full load of physics too. We *are* talking
about basic electricity here.

--
Keith

 

[John Larkin]

On Mon, 29 Sep 2008 14:15:17 -0700, StickThatInYourPipeAndSmokeIt
<Zarathustra@thusspoke.org> wrote:

On Mon, 29 Sep 2008 11:57:18 -0700 (PDT), Rose <couple7802002@yahoo.com
wrote:

On Sep 29, 9:59 am, bgold12 <bgol...@gmail.com> wrote:
Hey, I'm in 3rd year mechanical engineering and I still don't feel
like I have a strong understanding of what voltage is. Maybe someone
can help explain the concept.

I'm pretty sure I understand what charge is (it's just a fundamental
property of subatomic particles that affect the way they interact,
i.e. a charged particle induces a force on a surrounding charged
particle based on their charges (+e for a proton, -e for an electron,
and 0 for a neutron) and the distance and properties of the volume
between them), and I'm pretty sure I understand current, which is just
moving charges (I picture a bunch of electrons moving through a volume
between idle nuclei). But I don't get the concept of voltage. I know
it's produced from a separation of charges, and it is energy per
charge, or Joules/Coulomb, but where is the energy contained? How does
the coulomb of charged particles "have" this energy, and how is it
possible that there can be different amounts of energy associated with
a fixed amount of charged particles (i.e. you can have 10 joules/2
coulombs = 5 volts, but you can also have 20 joules/2 coulombs = 10
volts?)?

I hope that was clear, but it probably wasn't.

Thanks,

bgold12

What I can't understand is how a person can be in third year
engineering and not have a strong understanding of what voltage is.


Even worse... they somehow get good grades, and after they get their
degrees, some of them come to work at our place, and they STILL don't
understand it. Then they pay them engineering salaries and let them
design satellite gear!

Working at a high voltage power supply company did allow me to review,
and lock in a lot of basics. That was a good eight year experience in my
life.

Cool. Explain voltage to us.

John

 

[John Larkin]

On Mon, 29 Sep 2008 11:57:18 -0700 (PDT), Rose
<couple7802002@yahoo.com> wrote:

On Sep 29, 9:59 am, bgold12 <bgol...@gmail.com> wrote:
Hey, I'm in 3rd year mechanical engineering and I still don't feel
like I have a strong understanding of what voltage is. Maybe someone
can help explain the concept.

I'm pretty sure I understand what charge is (it's just a fundamental
property of subatomic particles that affect the way they interact,
i.e. a charged particle induces a force on a surrounding charged
particle based on their charges (+e for a proton, -e for an electron,
and 0 for a neutron) and the distance and properties of the volume
between them), and I'm pretty sure I understand current, which is just
moving charges (I picture a bunch of electrons moving through a volume
between idle nuclei). But I don't get the concept of voltage. I know
it's produced from a separation of charges, and it is energy per
charge, or Joules/Coulomb, but where is the energy contained? How does
the coulomb of charged particles "have" this energy, and how is it
possible that there can be different amounts of energy associated with
a fixed amount of charged particles (i.e. you can have 10 joules/2
coulombs = 5 volts, but you can also have 20 joules/2 coulombs = 10
volts?)?

I hope that was clear, but it probably wasn't.

Thanks,

bgold12

What I can't understand is how a person can be in third year
engineering and not have a strong understanding of what voltage is.

OK, Rose, explain voltage to us.

John

 

[Rose]

On Sep 29, 6:43 pm, John Fields <jfie...@austininstruments.com> wrote:

You were being much worse than cranky, you were being intentionally
disingenuous.

JF

I suppose you're right.

 

[Rose]

On Sep 29, 9:48 pm, "Jon Slaughter" <Jon_Slaugh...@Hotmail.com> wrote:

...

Nice job. Now he can go into fourth year.
No wonder our bridges are falling down.

When did one have to understand electricity to understand how to build a
bridge?

I'd rather the guy know squat about electricity and be a great bridge
builder than build shitty ass bridges cause he spent to much time trying to
learn about electricity for some school requirements to "broaden his
horizons".  He could have spent that time more wisely.

So are you trying to say that learning about electricity
is not a wise use of time?

 

[Rose]

On Sep 30, 12:02 am, Salmon Egg <Salmon...@sbcglobal.net> wrote:

According to the California Department of Consumer affairs, the initial
PE exam pass rate is lower for EE's than for any other branch of
engineering. Having found the exam relatively easy, I had a hard time
believing that. Nevertheless after seeing many of the posts on this
subject, I am no longer surprised.

Bill

--
Private Profit; Public Poop! Avoid collateral windfall!

My brother in law is a ME. He thinks banging the
mouse on the desk helps speed up the computer.