Rocket observations show that dust particles in Earth's upper atmosphere are often electrically charged. HINT (a) Find the distance separating two dust particles (in m) if each has a charge of +e and the Coulomb force between them has magnitude 1.90 ? 10?14 N. m (b) Calculate the mass (in kg) of one of the dust particles if this Coulomb force would accelerate it at 4.60 ? 108 m/s2. (In the upper atmosphere, effects from other nearby charges typically result in a small net force and acceleration.) kg