Solving a problem in physics section 70 point 30 electr

Solving a problem in physics section 70 point 30 electr

30. To the air condenser, the voltage at which U1 = 210 V, was connected in parallel with the same uncharged capacitor, but with a dielectric of glass. What is the dielectric constant of the glass if the voltage at the battery terminals becomes U = 30 V?

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Detailed solution. Decorated in Microsoft Word 2003. (Target decided to use formula editor)