Astronomical structures such as galaxies are shaped predominantly by gravitation…
PHYSICS · Single correct · AP · Physics 2: Algebra-based · Electric Force Field and Potential · Electric Force Field and Potential
Problem
Astronomical structures such as galaxies are shaped predominantly by gravitation rather than by electrostatic interactions. Which of the following best explains this observation?
(a) The gravitational force has a longer range than the electric force because electric fields are shielded by interstellar plasma, so gravity shapes galaxies.
(b) Coulomb’s constant k decreases with distance, causing electric forces to weaken more rapidly than the 1/r2 gravitational attraction.
(c) Macroscopic objects are typically electrically neutral, so net electric forces nearly cancel while gravitational forces add.
(d) Galaxies contain much more mass than net charge, so the larger amount of mass makes gravity the dominant interaction.