61. Spherical capacitor formed thin spheres with radii r1 = 1,0 cm and r2 = 5,0 cm, between which the potential difference U = 2,0 kV. Determine the strength E of the electric field at a distance r = 3,0 cm from the center of the capacitor.

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