Answer: 1/r³.
- A 1/r³
- B 1/r²
- C 1/r
- D 1/r⁴
Correct answer: A. 1/r³
Explanation: The axial field of a dipole varies as 1/r³.
Field lines always point from positive to negative charge, are denser where the field is stronger, and never cross; an isolated positive charge has lines radiating symmetrically outward, while a dipole's lines curve from the positive to the negative charge.
Concept context
Coulomb's law, electric field, potential, capacitors, Gauss's law.