Task id16510

Two metal concentric spheres located in air have radii r1 = 20 cm and r2 = 40 cm. The inner sphere contains a charge q1 = -30 nC, the outer sphere is charged to a potential φ2 = 600 V. Find the field strengths and potentials at points A , B and C (Fig.), located on the same straight line at distances lA = 10 cm, lB = 25 cm and lC = 50 cm from the center of the spheres.