Solving a problem in physics section 44 paragraph 54 el

54. A porcelain ball radius R = 10 cm is charged uniformly with a bulk density ρ = 15 nC / m3. Determine the strength of the electrostatic field: 1) at a distance r1 = 5 cm from the center of the sphere; 2) on the surface of the ball; 3) at a distance r2 = 15 cm from the center of the ball. Draw a graph of E (r). The dielectric constant ε = 5 porcelain.