Chapter 21, Problem 52A

To determine

To discuss: Strength of electric field indicated with electric field lines.

Explanation of Solution

Introduction:

Electric field lines:

The electric field lines are actually the line of force. They are imaginary in nature. To determine the direction of net field at any point, a tangent is drawn at that point.

The lines of electric field originate from the positive charge and terminates in the negative charge.

The electric field lines between a positive and negative charge is shown below.

Figure 1

The strength of electric field is dependent on the density of field lines. When the lines of electric field are closer, the electric field is strong and when the lines of electric field are farther, the electric field is weak.

In the above figure, the field lines are close near the charge so, the electric field is strong near the charge. Moving away from the charge results in decrease in field lines density and hence the electric field is also decreases.