A spherical shell of radius Ra carries a total charge qa uniformly distributed on its surface. A larger spherical shell of radiu
s Rb is concentric with the first and carries a charge qb uniformly distributed on its surface. (a) Use Gauss’ law to find E~ in all regions (do not forget the inside of the smaller shell!). (b) If qa=6nC, what should qb be for the electric field to be zero for r > Rb? (c) Sketch the electric-field lines for the situation in part (b).
The forces on the satellite are unbalanced. The centripetal force changes the direction of the satellite, from a straight line to a closed loop around the Earth.