The magnitude e of an electric field depends on the radial distance r according to e = a/r4, where a is a constant with unit volt-cubic meter. as a multiple of a, what is the magnitude of the electric potential difference between r1 = 1.71 m and r2 = 2.89 m?

In a simplified model of the human eye, the aqueous and vitreous humors and the lens all have a refractive index of 1.40, and all the refraction occurs at the cornea, whose vertex is 2.60 cm from the retina. what should be the radius of curvature of the cornea such that the image of an object 40.0 cm from the cornea’s vertex is focused on the retina?

Petroleum contains energy. a. light b. kinetic c. chemical d. mechanical

12. a body is a particular amount of matter. it can be a solid, liquid or gas. it can be described as existing in a. size and shape. b. motion and force c. time and space. d. location and movement.