A) \[k\frac{{{e}^{2}}}{{{r}^{3}}}r\]
B) \[-k\frac{{{e}^{2}}}{{{r}^{3}}}r\]
C) \[k\frac{{{e}^{2}}}{{{r}^{2}}}r\]
D) \[-k\frac{{{e}^{2}}}{{{r}^{2}}}r\]
Correct Answer: A
Solution :
\[F=-\frac{1}{4\pi \,\,{{\varepsilon }_{0}}}\frac{{{q}_{1}}{{q}_{2}}}{{{r}^{2}}}=r\] \[F=-k\frac{{{q}_{1}}{{q}_{2}}}{{{r}^{2}}}=r\] \[F=-k\frac{e.e}{{{r}^{2}}}\widehat{\mathbf{r}}=-k\frac{{{e}^{2}}}{{{r}^{2}}}\widehat{\mathbf{r}}\] \[\widehat{\mathbf{r}}=\frac{\mathbf{r}}{|\mathbf{r}|}=\frac{r}{r}\] \[F=-k\frac{{{e}^{2}}}{{{r}^{2}}}\cdot \frac{\mathbf{r}}{r}=-k\frac{{{e}^{2}}}{{{r}^{3}}}\mathbf{r}\]
You need to login to perform this action.
You will be redirected in
3 sec
