A capacitor is made from two hollow, coaxial, iron cylinders, one inside the other. The inner cylinder is negatively charged and the outer is positively charged; the magnitude of the charge on each is 11.5 pC. The inner cylinder has a radius of 0.550 mm, the outer one has a radius of 4.00 mm, and the length of each cylinder is 15.0 cm.

(1) What is the capacitance? Use 8.854×10−12 F/m for the permittivity of free space.
(2) What applied potential difference is necessary to produce these charges on the cylinders?

Explanation:

a.

Given the permittivity constant to be ,The capacitance of a of length, is given by the equation:

where is the radius of the outer cylinder and the radius of the inner cylinder.

The values are given as:

Substitute in our capacitance equation:

Hence the capacitance is

b. The charge on the capacitance is related to the potential difference across it. The potential difference is expressed using the equation:

,

From a above, we already have our capacitance value,

We substitute in the pd equation:

Hence, the applied potential difference is 2.7344V

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.