Question 9

A system has two charges q_{A} = 2.5 × 10^{−7} C and q_{B} = −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?

Answer

According to the figure given below both the charges can be located in a coordinate frame of reference.

At A, amount of charge, q_{A} = 2.5 × 10^{−7}C (Given)

At B, amount of charge, q_{B} = −2.5 × 10^{−7} C (Given)

Total charge of the system,

q = q_{A} + q_{B} = 2.5 × 10^{-7} C − 2.5 × 10^{−7} C = 0

Distance between two charges at points A and B,

d = 15 + 15 = 30 cm = 0.3 m

Electric dipole moment of the system is given by,

p = q_{A} × d = q_{B} × d = 2.5 × 10^{−7} × 0.3 = 7.5 × 10^{−8} C m along positive z-axis

Therefore, the electric dipole moment of the system is 7.5 × 10^{−8} C m along positive z−axis.

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saravanan
2019-06-15 19:43:02

it is simple 15-(-15)=30 cm answer is 0.03 m

sneha
2019-06-15 15:01:07

how to find distance in graph points?????????????????????????

Adriz
2018-12-10 18:38:00

Exactly chaitanya

Chaitanya
2017-10-21 19:35:27

The dipole must be along negative z axis

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