The diagram shown represents a portion of a wire in a circuit. A current is flowing in the wire in the direction shown. Under the convention that it is positive charge that flows the electric field points in the direction of the current. How can the electric field change direction where the wire bends?
A) There is an excess of negative charge in the center of the wire.
B) There is an excess of positive charge at the bottom end of the wire.
C) There is an excess of negative charge at the right end of the upper portion of the wire.
D) There is an accumulation of positive charge on the surface, particularly at the bend, such that the sum of electric fields gives the new electric field.
E) There is an accumulation of electrical potential as the current traverses the wire: The higher potential in the lower half is the source of the field.

Question

The diagram shown represents a portion of a wire in a circuit. A current is flowing in the wire in the direction shown. Under the convention that it is positive charge that flows the electric field points in the direction of the current. How can the electric field change direction where the wire bends? 
A) There is an excess of negative charge in the center of the wire. 
B) There is an excess of positive charge at the bottom end of the wire. 
C) There is an excess of negative charge at the right end of the upper portion of the wire. 
D) There is an accumulation of positive charge on the surface, particularly at the bend, such that the sum of electric fields gives the new electric field. 
E) There is an accumulation of electrical potential as the current traverses the wire: The higher potential in the lower half is the source of the field.

Quizplus · Accepted Answer

When the wire bends, there is an accumulation of charge on the surface, particularly at the bend. This accumulation of charge can be either positive or negative depending on the direction of the bend. The sum of the electric fields from these charges creates a new electric field that is different in direction from the original field. Therefore, the electric field changes direction where the wire bends.

The Diagram Shown Represents a Portion of a Wire in a Circuit