Solving a problem in physics section 74 point 6 electr

Solving a problem in physics section 74 point 6 electr

6. A ball weighing 90 mg is suspended on a non-conductive thread and has a charge of 10 nC. After a point charge of a different sign was placed under the ball at a distance of 10 cm from it, the thread tension doubled. Find the magnitude of this charge.

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