Answer:
a) 0.45 μC b) 2.81*10¹² absent electrons.
Explanation:
The total net charge on the 4 spheres, is just the algebraic sum of the individual charges:
Q = Q₁ +Q₂ + Q₃ +Q₄ = +1.0 μC + 5.4 μC -2.6 μC -2.0 μC = +1.8 μC
After being brought in contact each other and then separated, the total charge must be the same as before, i.e., + 1.8 μC.
As the spheres are identical and assumed perfect conductors, at being put in touch each other, there will be a free movement of charges, trying to bring all spheres to a neutral state.
Due to the symmetry of the problem, after being separated, all spheres must carry the same charge, as follows:
Q₁ = Q₂ = Q₃ = Q₄ = Q/4 = +1.8 μC / 4 = +0.45 μC
b) As each sphere has a resulting positive charge, this means that they have a defect of electrons, which number can be found as follows:
[tex]N =\frac{Q}{e} =\frac{0.45e-6C}{1.6e-19C} = 2.81e12 electrons[/tex]
