Answer to Question #262599 in Electricity and Magnetism for Moe

Question

PP1//1

Two identical conducting spheres, one that has an initial charge +Q, the other initially uncharged, are brought into contact. What is the new charge on each sphere?

(a) +Q

(b) +Q/2

(c) zero

(d) -Q/2 (e) -Q

Answer 1

When two identical conducting spheres are brought into contact the charge distribution is same. Because their area is also same.

Surface charge density for each conductor is $Q/A$ . So, when they are in contact, total surface charge density is $Q/2A$ .

So that if Area is doubled, charge is also divided on both conductor in same way.

Thats why answer is $+Q/2.$