A system has two charges qA = 2.5 × 10–7C and qB = –2.5 × 10–7 C located at points A: (0, 0, –15 cm) and B: (0,0, + 15 cm), respectively. What are the total charge and electric dipole moment of the system?
The charge at point A, qA = 2.5 × 10–7C
The charge at point B, qB = –2.5 × 10–7 C
∴ the total charge of the system, Qnet = qA + qB
Qnet = 2.5 × 10–7C + (–2.5 × 10–7 C)
Qnet = 0
The distance between these two charges = Distance between point A and B, d = 15 + 15
d = 30 cm = 0.3 m
The electric dipole moment can be defined as the measure of the separation of positive as well as negative charges within a specific system. It tells us about the given system’s overall polarity.
The electric dipole moment of the system, p = qA x d = qb x d
p = 2.5 × 10–7C x 0.3
∴ p = 7.5 x 108 C-m along the positive z-axis
Hence, the electric dipole moment of this system is 7.5 x 108 C-m along the positive z axis.