Which statement best describes the relationship between an object's density and its index of refraction? as the optical density increases, the refractive index decreases. as the tendency of the atoms to absorb energy before reemitting it increases, the refractive index increases. as the mass per unit volume of the substance increases, the refractive index decreases. as the physical density of the substance increases, the refractive index increases.

Intro: a solid ball of radius rb has a uniform charge density ρ. part a: what is the magnitude of the electric field e(r) at a distance r> rb from the center of the ball? express your answer in terms of ρ, rb, r, and ϵ0. part b: what is the magnitude of the electric field e(r) at a distance r express your answer in terms of ρ, rb, r, and ϵ0. part c: let e(r) represent the electric field due to the charged ball throughout all of space. which of the following statements about the electric field are true? check all that apply. e(0) = 0 e(rb)=0 limr→∞e(r)=0 the maximum electric field occurs when r=0 the maximum electric field occurs when r=rb the maximum electric field occurs as r→∞.