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Capacitor charging itself?

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Potential difference?

But that would make it a power source.

My first thought was dielectric absorbtion, but that doesn't fit the question either.
 

Harald Kapp

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It may be a trick question. The answer may simply be "impossible".
 

Bluejets

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The atmospheric pd was originally used in sensors for autopilots.
If I remember correctly the Israelis produced some of the first.

I clearly remember it as there was one hell of a hallabalu over the fact that the sensors contained minute radio active particles, probably much like some of the older smoke detectors.

ELECTROSTATIC AUTOPILOTS Voltage differences as large as several kilovolts can appear between insulated sensors located on the wing tips of an aircraft when it banks in the earth's atmospheric electric field. The sensed differences can be converted into feedback signals to provide a vertical reference for autopilots. Electrostatically stabilized radio-controlled aeromodels and remotely piloted vehicles have been used to investigate the characteristics of electric fields in fair and adverse weather as well as in regions of severe electrical disturbances near thunderstorms. The operational principles of this stabilization method are described here.

http://www.jhuapl.edu/techdigest/views/pdfs/V05_N2_1984/V5_N2_1984_Hill_Electro.pdf
 

nati levia

Mar 22, 2018
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Is English your native language? WTF is a "capacitor witch"? Some sort of paranormal capacitor? How do you (or your teacher) expect to add energy to any capacitor without using a power source? Is this an advanced course in practical magic, or are you actually studying electronics? Please photograph and post a picture of the actual test question (and its context) since you are "reading it right now..."

On another thread, this student found out that this same teacher made a mistake about capacitors.
Then maybe this teacher has a screwed up idea about charging a capacitor?
I think so.
 

nati levia

Mar 22, 2018
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Heya.
I'm a student at high school, I'm over most of the school (at knowledge) and the teacher gave me a test.
The test is easy but there was one question that i don't know (hats the question that summarizes the test),
The question is: How do you recharge a capacitor by itself?.

I must pass the test in 100% so i can go to the collage that i always wanted to go.


Quick update guys, I passed! the answer was: Physics says that electricity has to come from somewhere, And this is just like those fake free energy videos on YouTube. What i mean by that: A capacitor cannot charge itself"

I passed
Is English your native language? WTF is a "capacitor witch"? Some sort of paranormal capacitor? How do you (or your teacher) expect to add energy to any capacitor without using a power source? Is this an advanced course in practical magic, or are you actually studying electronics? Please photograph and post a picture of the actual test question (and its context) since you are "reading it right now..."

This is the scanned version of the test.
https://docs.google.com/document/d/1BjyaeVrar4c1x0U9xqAoB9li-83VFTSO4nvQzmXWPm8/edit?usp=sharing
 

nati levia

Mar 22, 2018
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Heya.
I'm a student at high school, I'm over most of the school (at knowledge) and the teacher gave me a test.
The test is easy but there was one question that i don't know (hats the question that summarizes the test),
The question is: How do you recharge a capacitor by itself?.

I must pass the test in 100% so i can go to the collage that i always wanted to go.
Heres the test.

https://docs.google.com/document/d/1BjyaeVrar4c1x0U9xqAoB9li-83VFTSO4nvQzmXWPm8/edit?usp=sharing
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Wow, LEDs rated at 20 MegaAmps, a 55MegaHenry inductor,

Did you give at least 2 answers to Q3?

How many nΩ did you calculate for Q4?

Did Q5, 8, 9, and 10 all have pretty much the same answer?

How long an arc did you estimate you'd pull in Q7?

What language does your teacher speak?
 

Kiwi

Jan 28, 2013
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No wonder the kids of today have trouble with spelling, grammar, and punctuation.
Your teacher needs to learn the difference between "m" and "M" prefixes for SI units.

As asked previously, is English your teacher's first language?

Q10 is easy. It's a flux capacitor.:D
 
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