A) \[x=\frac{a}{\sqrt{2}}\]
B) \[x=\sqrt{2}a\]
C) \[x=\,\,\frac{\sqrt{2}a}{\sqrt{2}-1}\]
D) \[x=\,\,\frac{\sqrt{2}a}{\sqrt{2}+1}\]
Correct Answer: C
Solution :
Suppose the field vanishes at a (distance x), we have \[\frac{kq}{{{x}^{2}}}\,\,=\,\,\frac{kq/2}{{{(x-a)}^{2}}}\] \[or\,\,\,2{{(x-a)}^{2}}={{x}^{2}}\,\,\,\,\,or\,\,\,\,\sqrt{2}(x-a)=x\] \[or\,\,\,(\sqrt{2}-1)x=\sqrt{2}\,a\,\,\,\,\,or\,\,\,\,x=\left( \frac{\sqrt{2}\,a}{\sqrt{2}-1} \right)\]You need to login to perform this action.
You will be redirected in
3 sec