Electricity and Magnetism
# Electric Fields

$200 \text{ N/C}$ points to the left as shown in above figure. When the distance between points $A$ and $B$ is $d= 5 \text{ cm},$ what is the difference in potential $V_A - V_B$ between points $A$ and $B?$

A uniform electric field ofA charge of $6.0 \text{ nC},$ is initially at a point that is $r_1 = 3.0 \text{ m},$ away from a charge of $1.0 \text{ nC}$ moves further away to a point where the distance is $r_2= 7.0 \text{ m}.$ What is the approximate potential difference between the two points.

Assume that electric constant is $\epsilon_0 = 8.9 \times 10^{-12} \text{ F/m}.$

A 9-V battery has an electric potential difference of $9\text{ V}$ between the positive and negative terminals. How much kinetic energy **in J** would an electron gain if it moved from the negative terminal to the positive one?

**Details and Assumptions:**

- The charge on the electron is $-1.6 \times 10^{-19}~\mbox{C}$.
- You may assume energy is conserved (so no drag or energy loss due to resistance for the electron).

$q_1 = 2.0 \text{ nC}, q_2 = 5.0 \text{ nC}$ and $q_3 = 4.0 \text{ nC}$ are placed at the three corners of a square with side length $d = 7 \text{ m}.$ Find the approximate potential at the point $A.$

As shown in the above figure, three point chargesAssume that electric constant is $\epsilon_0 = 8.9 \times 10^{-12} \text{ F/m}$ and $\sqrt{2}$ is $1.4.$