Answer: square.
- A square
- B cube
- C first power
- D fourth power
Correct answer: A. square
Explanation: F ∝ 1/r², the inverse square of the separation.
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.