Solving a problem in physics section 73 point 87 electr

Solving a problem in physics section 73 point 87 electr

87. A small ball weighing 0.1 g is suspended on a silk thread. A charge of 50 CGEQ is communicated to the ball. How close should the charge of the same name be brought to it from below so that the tension force of the thread is halved? The charges are in a vacuum.

Additional information:

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