64. Two small charged balls in the vacuum of the same mass, whose charges q1 = q2 = 30 nC, are suspended at one point on light silk threads of the same length l = 15 cm. If the balls are separated so that the angle between the threads is α = 90 ° , then the mass m of each ball is ... mg.

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