Question

1. Why can electric fields not cross each other?

A. Many electric field lines can exist at any given point in space.

B. No electric field lines can exist at any given point in space.

C. Only a single electric field line can exist at any given point in space.

D. Two electric field lines can exist at the same point in space.

2. By considering the molecules of an insulator, explain how an insulator can be overall neutral but carry a surface charge when polarized.

A. Inside the insulator, the oppositely charged ends of the molecules cancel each other.

B. Inside the insulator, the oppositely charged ends of the molecules do not cancel each other.

C. The electron distribution in all the molecules shifts in every possible direction, leaving an excess of positive charge on the opposite end of each molecule

D. The electron distribution in all the molecules shifts in a given direction, leaving an excess of negative charge on the opposite end of each molecule

Answer 1

1. Option C.

Explanation: Elextric field line is the imaginary line along which a test charge (which is positive and small) moves in the presence of external electric filed. As it can move only one direction at an instant /point , any any point there is only one electric field line. Electric field lines never intersect

2. Option A.

Explanation : when insulating material is polarizes each molecule become a dipole.

Each molecule (or dipole ) orient in the direction of external electric field. i.e. if electric field is applied from Left to right

Each molecule orient to have positive terminal on right side and negative terminal on left side.