Much of the material making up Saturn’s rings is in the form of tiny dust grains having radii on the order of 10-6m. These grains are located in a region containing a dilute ionized gas, andthey pick up excess electrons. As an approximation, suppose each grain is spherical, with radius R = 1.0 × 10-6m. How many electrons would one grain have to pick up to have a potential of -400 V on its surface (taking V = 0 at infinity)?

Imagine an isolated positive point charge q (many times larger than the charge on a single proton). there is a charged particle a (whose charge is much smaller than charge q) at a distance from the point charge q. on which of the following quantities does the magnitude of the electric field created by charge q at particle a's position depend? check all that apply.the type of the charge on the charged particle athe relative orientation between q and a (while the distance between q and a is fixed)the specific location of the charged particle a (while the distance between q and a is fixed)the amount of the charge on the point charge qthe specific location of the point charge q (while the distance between q and a is fixed)the distance between the point charge q and the charged particle athe amount of the charge on the charged particle a