--
Indeed, since:
q_tot = integral I*dt from 0 to infty
should read:
q_tot = integral I*dt from 0 to t,
I believe. ;)
From:
http://www.thefreedictionary.com/ampere-second
"ampere-second - a unit of electrical charge equal to the amount of
charge transferred by a current of 1 ampere in 1 second."
So, for one coulomb of charge to be transferred through a one ohm
resistor in one second, the voltage would have to remain at one volt
for one second.
Such is not the case when a one farad capacitor is charged to one volt
and connected across a 1 ohm resistor for one second, since the
voltage will decay from 1V to 0.368V during that time and there'll be:
Q = CV = 1F * 0.368V = 0.368 coulomb
still left in the cap when it's disconnected.
Of course not, but Larkins original statement was "eventually", not "after one second". You are the only one to add this condition, obviously if you stop discharging the cap early you will not get all the charge out!
One ampere-second does not have to mean that "one amp flowed for one second", It means an amount of charge *equal to* that transferred by one amp flowing for one second. It could be 2 amps for half a second, 10 amps for 0.1s, 1000 amps for 1 millisecond.
"Slap a 1-ohm resistor across the 1F/1v cap and discharge it. You'll get 1 ampere-second out of it eventually."
How did you miss the words "discharge" and "eventually"? I worded the situation as carefully as I could, figuring some whiney dork or another would get pretend-lawyer pickey. Sigh.
How many ampere-seconds would you get if it was discharged by a 10 ohm resistor?
"Side" with whomever you like. But both "laws" apply simultaneously. ...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Obama isn't going to raise your taxes...it's Bush' fault: Not re-
newing the Bush tax cuts will increase the bottom tier rate by 50%
The photons entered the game from "outside the box" as someone opined.
As for your "explanation" above... :-(
If I'm so wrong and Larkin is so right, WHY don't Hill and Hobbs jump to his defense? ...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Obama isn't going to raise your taxes...it's Bush' fault: Not re-
newing the Bush tax cuts will increase the bottom tier rate by 50%
Right. This being an electronics design group, and specifically a discussion about capacitors on schematics and not electrostatics, I assume that when we talk about the charge on a capacitor, it's zero if there's no voltage across its terminals, and any subsequent charge stored by the cap is equal to the integral of applied current.
Q = CV = integral(I.dt)
where V is the voltage across the cap C in farads, V volts, t seconds
or in the rectangular case,
Q = CV = IT
starting from some initial point of Q=0, V=0.
Q is measured in coulombs, which are dimensionally ampere-seconds.
Given this definition of charge on/in a capacitor, one could further define the "total charge" in a circuit somehow. Carefully.
I think the highest voltage Tek CRT was around 28KV, in the 519. Relativistic effects are still small at 30KV, about 5% on mass, 1.5% on velocity, probably small enough to ignore.
--
I didn't miss them, I just thought someone as vague as you are coudn't
possibly have meant "coulomb" since it's a much less confusing term.
So you prefer ampere-second to coulomb?
Nowhere did I say that charge cannot be removed (via the resistor, or whatever) from a capacitor... you MORONIC OBFUSCATOR!
Certainly! Do you? ...Jim Thompson
-- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at
formatting link
| 1962 | Obama isn't going to raise your taxes...it's Bush' fault: Not re- newing the Bush tax cuts will increase the bottom tier rate by 50%
But they don't carry charge. They do carry energy - so are you saying you can convert energy into "charge"? I agree - this is true for "Q=CV" "charge-as-used-in-electronics", but false for "number of electrons - number of protons" physicists charge.
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.