Suppose a stream of negatively charged powder was blown through a cylindrical pipe of radius r = 7.5 cm. assume that the powder and its charge were spread uniformly through the pipe with a volume charge density rho. (a) find an expression for the electric potential as a function of the radial distance r from the center of the pipe. (the electric potential is zero on the grounded pipe wall.) (b) for the typical volume charge density rho = -3.7 × 10-3 c/m3, what is the difference in the electric potential between the pipe's center and its inside wall?

A)

B)

Explanation:

a) using Guass law

Here

Volume charge density is given as

net charge is given as

therefore

After solving electric field equation we get

b) electric potential difference is given as

at r = 0

jupiter is the largest planet in our solar system, having a mass and radius that are respectively, 318 and 11.2 times that of earth. suppose that an object falls from rest near the surface of each planet and that the acceleration due to gravity remains constant during the fall. each object falls the same distance before striking the ground. determine the ratio of the time of fall on jupiter to that on earth.