A scientist is researching what happens when a neutral metal sphere located on an insulated stand is touched by a negatively rod. The set up for the experiment is shown in the picture below. What will happen to the excess electrons when the negatively charged rod touches the metal sphere? (The excess electrons will move from the sphere to the rod and stay close together; the excess electrons will move from the sphere to the rod and spread out; the excess electron will move from the rod to the sphere and stay close together; the excess electrons will move from the rod to the sphere and spread out)

Answer 1

When a negatively charged rod touches a neutral metal sphere, the excess electrons from the rod will move to the sphere. This is because like charges repel, and since the sphere is neutral, it can accept excess electrons.

Once the rod makes contact with the sphere, some of the excess electrons from the rod will flow onto the sphere due to the attraction between the electrons (on the rod) and the positive charges in the metal sphere (since the metal is neutral overall).

Once transferred, these electrons will spread out across the surface of the sphere because in a conductor, charges will spread out evenly to minimize repulsion. Therefore, the excess electrons will not stay close together; they will redistribute themselves over the surface of the sphere.

In summary, the correct statement is: the excess electrons will move from the rod to the sphere and spread out.