One electrical task

[ValeryOchkov]

See please Prime 6 in attach.

How to solve this task not with SI but with CGS (not with F but with cm)?

Very interesting article about this problem Dmitry Sivukhin "About SI" 1974 

[ValeryOchkov]

Ops. I did not know that!

[Werner_E]

Hmmm...

Is this equivalent to the old CGS unit "statfarad" ?

I believe that until the middle of the last century it was customary to specify smaller capacitors in cm and not in pF.
But it is still irritating and confusing these days ...

BTW, I have read and was not aware of the fact that in the past it was also common to specify inductances in cm. 1 cm = 1 nH

[ValeryOchkov]

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@Werner_E wrote:

Hmmm...

BTW, I have read and was not aware of the fact that in the past it was also common to specify inductances in cm. 1 cm = 1 nH

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Not cm (length) but time^2/length

And with C

PS

Дivertissement

[Werner_E]

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@ValeryOchkov wrote:

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@Werner_E wrote:

Hmmm...

BTW, I have read and was not aware of the fact that in the past it was also common to specify inductances in cm. 1 cm = 1 nH

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Not cm (length) but time^2/length

No, just cm. I was talking about the former (or is it still relevant?) usage in the CSG system.

For example see here: https://www.translatorscafe.com/unit-converter/ms-MY/inductance/

For the centimeter-gram-second (CGS) system, including the extended electromagnetic (EMU) and Gaussian systems of units, inductance is measured in cm (1 H = 10⁹ cm; 1 cm = 1 nH). In some cases, units called abhenry are used as an equivalent of a centimeter. In addition, in the extended electrostatic CGS (ESU) the unit for inductance is either left blank or referred to as stathenry. 1 stathenry ≈ 8.987552·10⁻¹¹ henry. The coefficient used to convert between stathenry and henry equals the square of the speed of light measured in cm/second, and multiplied by 10⁻⁹.

[ValeryOchkov]

I would like to see the calculation with the answer L = 7 cm.