Answer:
1) Q_c = - ½ Q
, 2) Q_c = + ¼ Q
, 3) Q_c= 3/8 Q
Explanation:
For this exercise we must use that equal charges repel and charges with different signs attract. When two objects are in contact, the charges are evenly distributed between them.
Scenario 1.
when the two spheres touch the charge -Q is distributed between them, when separating each sphere has a charge = -1/2 Q
as there are no more interacts sphere C its charge is
Q_c = - ½ Q
Scenario 2
when the two spheres touch the charge -Q is distributed between them, when separating each one has a charge
Q_a = Q_d = - ½ Q
now the sphere D and C touch the charge is Q_net = -1/2 Q + Q = + ½ Q
when separating each sphere has half the charge
Q_d = Q_c = + ¼ Q
since sphere C has no more interaction, its charge is
Q_c = + ¼ Q
Scenario 3
A and B touch the net charge is Q_net = - Q + 0 = - Q
when parting
Q_a = Q_b = - ½ Q
now B and D touch, the charge is Q_net = - ½ Q +0 = - ½ Q
when parting
Q_b = Q_d = - ¼ Q
finally C and D touch
the net charge is Q_net = Q- ¼ Q = ¾ Q
when separating each one is left with half the load
Q_c = Q_d = 3/8 Q
Q_c= 3/8 Q
