Question

A -17nC charge is located at the origin.

1. What is the strength of the electric field at the position (x,y)=(0cm,5.0cm)?

Express your answer using two significant figures.

2. What is the strength of the electric field at the position (x,y)=(?5.0cm,?5.0cm)?

Express your answer using two significant figures

3. What is the strength of the electric field at the position (x,y)=(?5.0cm,5.0cm)?

Express your answer using two significant figures

Answer 1

A) E = KQ/R^2

= -17*10^-9 * 9*10^9 / 0.05/0.05

= -61200 i

b) E = -61200i -61200j

c) E = -61200i +61200j

Answer 2

we have $\bar{E}=\frac{Kq}{r^{2}}\hat{r}$ where $K=9*10^{9}Nm^{2}C^{-2}$ and $q=-17nC$

hence

1. $\bar{E}=\frac{Kq}{r^{2}}\hat{r}=6.12*10^{4}V/m(-\hat{i})$

2. $\bar{E}=\frac{Kq}{r^{2}}\hat{r}=2.16*10^{4}V/m(\hat{i}+\hat{j})$ here $r=5\sqrt{}2$

3. $\bar{E}=\frac{Kq}{r^{2}}\hat{r}=2.16*10^{4}V/m(\hat{i}-\hat{j})$ here also $r=5\sqrt{}2$