Two uncharged, conducting spheres are separated by a distance d. When charge −Q is moved from sphere A to sphere B, the Coulomb force between them has magnitude F0.

(a)Is the Coulomb force attractive or repulsive?

attractive repulsive

(b) If an additional charge −Q is moved from A to B, what is the ratio of the new Coulomb force to the original Coulomb force,(c) If sphere B is neutralized so it has no net charge, what is the ratio of the new to the original Coulomb force,

a) the force will be repulsive

b) the ratio of the new force to the old force will be 2

c) O

Explanation:

a) since charge -Q is moved from A to B, this implies that sphere A is negatively charged. The two spheres are now negatively charged and will repel themselves.

b) initial force will be -q(-Q)/d2

Adding extra charge -Q will cause change on B to become -2Q

The new force will be - 2Q(-q)/d2

Dividing new force by old force will give 2

C) if B is neutralized, the net charge becomes 0 and there will be no force on it.

concave lenses are used here. they spread the light out before it reaches the convex lens in the eye, therefore letting the image focus directly on the retina. hyperopia is known to you probably as farsightedness.

temp rises, and expansion