Two small charged metal spheres A and B are situated in a vacuum. The distance between the centres of the spheres is 12.0 cm, as shown in Fig. 4.1.
The charge on each sphere may be assumed to be a point charge at the centre of the sphere. Point P is a movable point that lies on the line joining the centres of the spheres and is distance x from the centre of sphere A. The variation with distance x of the electric field strength E at point P is shown in Fig. 4.2.
1. How to know that the spheres are conductors ??
2. How to know that the charges are both positive or both negative ??
For part1: electric field strength change thus it conducts.
For part2: as electric field strength change from positive to negative, they are both positive.
It is correct ??