Two spherical conductors B and C having equal radii and cayying equal charges on them repel each other with a force F when kept apart at some distance. A third spherical conductor having same radius as that B but uncharged is brought in contact with B, then brought in contact with C and finally removed away from both. The new force of repulsion between B and C is

Charges on identical spheres A and B are equal. When the separation between them is 1 m, the repulsion between them is 80 N. Now, another identical and uncharged sphere C is brought in contact with A and then separated. Then, C is brought in contact with B and then separated. What will be the new force between A and B ?

A charged metallic sphere A is suspended by a nylon thread. Another charged metallic sphere B held by an insulating handle is brought close to A such that the distance between their centres is 10 cm, as shown in figure (a). The resulting repulsion of A is noted (for example, by shining a beam of light and measuring the deflection of its shadow on a screen). Spheres A and B are touched by uncharged spheres C and D respectively, as shown in figure (b). C and D are then removed and B is brought closer to A to a distance of 5.0 cm between their centres, as shown in figure (c). What is the expected repulsion of A on the basis of Coulomb's law ? Spheres A and C and spheres B and D have identical sizes. Ignore the sizes of A and B in comparison to the separation between their centres.

Two solid sphere of same size of a metal are placed in contact by touching each other prove that the gravitational force acting between then is directly proportional to the fourth power of their radius.

A conducting sphere S_1 of radius r is attached to an insulating handle. Another conduction sphere S_2 of radius R is mounted on an insulating stand. S_2 is initially uncharged. S_1 is given a charge Q brought into contact with S_2 and removed. S_1 is recharge such that the charge on it is again Q and it is again brought into contact with S_2 and removed. This procedure is repeated n times. a. Find the electrostatic energy of S_2 after n such contacts with S_1 . b. What is the limiting value of this energy as nrarroo ?

Two metal spheres, one of radius R and the other of radius 2R, both have same surfac charge density sigma . They are brought in contac and separated. What will be new surface charge densites on them ?

A charged metallic sphere A is suspended by a nylon thread another charged metallic sphere b held by an insulating centers is 10 cm as shown in Fig. 1.7(a). The resulting repulsion of A is noted (for example, by shining a beam of light and measuring the deflection of its shadow on a screen). Spheres A and B are touched by uncharged spheres C and D respectively, as shown in Fig. 1.7(b). C and D are then removed and B is brought closer to A to a distance of 5.0 cm between their centers, as shown in Fig. 1.7(c). What is the expected repulsion of A on the basis of Coulomb’s law? Spheres A and C and spheres B and D have identical sizes. ignore the sizes of a and b in comparison to the separation between their centers

(a) Two insulated charged copper spheres a and b have their centres separated by a distance of 50 cm what is the nutual force of electrostatic repulsion if the charge on each is 6.5 xx10^(-7) c the radii of a and b negligible compared to the distance of separation (b) what is the force of repuslion if each spere is charged double the above amount andf the distance between them is haved