Question

Hollow Spheres Part A Consider the following arrangement of two conducting hollow spheres with a point charge of Qo-4.90 HC at the center. The inner sphere has a radius of 0.011 m and carries a net charge of Q1- -1.30 uC. The outer sphere has a radius of 0.061m and carries a net charge of Q2 -6.30 HC Lo Calculate the magnitude of the electric field at point A located at a distance 0.021 m from the center. 7.34x107 N/C Part B Calculate the surface charge density on the outer surface of the outer sphere. Neglect the thickness of the sphere. 222 C/m*2 Submit Answer Incorrect. Tries 1/6 Previous Tries

Answer 1

given

Q_o = 4.9 uC

Q₁ = - 1.3 uC

Q₂ = 6.3 uC

inner radius = 0.011 m

outer radius = 0.061 m = R

r = 0.021 m

a )

using equation

E_A = k ( Q_o + Q₁ ) / r²

= 9 x 10⁹ x ( 4.9 x 10^-6 - 1.3 x 10^-6 ) / 0.021²

E_A = 7.3469 x 10⁷ N/C

b )

$\sigma$ = Q / A

= ( Q_o + Q₁ + Q₂ ) / R²

= ( 4.9 - 1.3 + 6.3 ) x 10^-6 / 0.061²

$\sigma$ = 2.3945176 x 10⁷ N/C