Determine the force between
the point charge and ungroudned and uncharged sphere.
Take radius of sphere to be R and the distance between the point charge
and the center of the sphere to be d.
2) In a grounded block of conductor
there is a spherical hollow (see the sketch).
The center of the hollow is at point O,
and the radius of the sphere (i.e. distance between points O and A is R.
At a distance d from point O placed a charge q. Find the charge density
of induced charges at point A.
3) Two infinite conducting plates are perpendicular to each other.
A charge q is placed distance a from their intersection,
along the bisector.
Find the force F acting on the charge.