Answer: four.
- A four
- B two
- C half
- D eight
Correct answer: A. four
Explanation: F ∝ q₁q₂, so doubling both multiplies the force by 4.
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.