Ametallic object is given a positive charge by the process of induction, as illustrated in figure 18.8. (a) does the mass of the object increase, decrease, or remain the same? why? (b) what happens to the mass of the object if it is given a negative charge by induction? explain.

a. In the process of induction, metal objects are positive because electrons are pushed out of the object to the earth. The mass of the object decreases by an amount equal to the mass of the electrons leaving the metal object.

b. During the induction process, electrons are drawn from the earth to the object, so that the metal object becomes negative. The mass of the object increases by an amount equal to the mass of "excess" electrons dragged onto the object.

An  atom  (ours, not carroll's) consists of a positively charged  nucleus, surrounded by one or more negatively charged particles called  electrons. the positive charges equal the negative charges, so the atom has no overall charge; it is electrically neutral. most of an atom's mass is in its nucleus; the mass of an electron is only 1/1836 the mass of the lightest nucleus, that of hydrogen. although the nucleus is heavy, it is quite small compared with the overall size of an atom. the radius of a typical atom is around 0.1 to 0.25 nanometres (nm), whereas the radius of a nucleus is about 10-6  nm.  *  if an atom were enlarged to the size of the earth, its nucleus would be only 200 feet in diameter and could easily rest inside a small football stadium.read more on -