Two identical spheres carry charges of +0.6 coulomb and -0.2 coulomb, respectively. if these spheres touch, the resulting charge on the first sphere will be

1. +0.8 c 2. +0.2 c 3. -0.3 c 4. +0.4 c

2. +0.2 C

Explanation:

When the two spheres touch, the total charge will be redistributed such that the two spheres are at same potential:

The potential can be rewritten as ratio between the charge on the sphere (Q) and the capacitance of the sphere (C):

Since the two spheres are identical, they have same capacitance:

So we can write

And since the total charge is

And this charge will be redistributed equally on the two spheres (), we have

the answer is a. at the equator

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.