Question

The force on an electron at a point in
electric field is 1.6x10-19 N. The field at
the point is
1 V/m
0.5 V/m
2 V/m
4 V/m​

Answer 1

Answer:

By the end of this section, you will be able to:

Describe the relationship between voltage and electric field.

Derive an expression for the electric potential and electric field.

Calculate electric field strength given distance and voltage.

The figure shows two vertically oriented parallel plates A and B separated by a distance d. The plate A is positively charged and B is negatively charged. Electric field lines are parallel between the plates and curved at the ends of the plates. A charge q is moved from A to B. The work done W equals q times V sub A B, and the electric field intensity E equals V sub A B over d and potential difference delta V equals q times V sub A B.

Figure 1. The relationship between V and E for parallel conducting plates is

E

=

V

d

. (Note that ΔV = VAB in magnitude. For a charge that is moved from plate A at higher potential to plate B at lower potential, a minus sign needs to be included as follows: –ΔV = VA – VB = VAB. See the text for details.)

In the previous section, we explored the relationship between voltage and energy. In this section, we will explore the relationship between voltage and electric field. For example, a uniform electric field E is produced by placing a potential difference (or voltage) ΔV across two parallel metal plates, labeled A and B. (See Figure 1.)

Examining this will tell us what voltage is needed to produce a certain electric field strength; it will also reveal a more fundamental relationship between electric potential and electric field. From a physicist’s point of view, either ΔV or E can be used to describe any charge distribution. ΔV is most closely tied to