A7.0 mm -diameter copper ball is charged to 40 nc. what fraction of its electrons have been removed? the density of copper is 8900kg/m^3.

Explanation:

Let the mass of copper ball is "m" gram

now the total number of copper atom present in the ball is given as

now the total number of electrons in one copper atom is 29

so total number of electrons in given sample of copper ball is

now diameter of the ball is 7.0 mm

density of the ball =

now we have

now we have

now the charge on the copper ball is 40 nC

so the number of electrons removed

so the fraction of number of electrons removed is given as