A) \[-\frac{4{{q}^{2}}}{\sqrt{2}\pi {{\varepsilon }_{0}}l}\]
B) \[\frac{\sqrt{3}{{q}^{2}}}{4\pi {{\varepsilon }_{0}}l}\]
C) \[\frac{4{{q}^{2}}}{\sqrt{2}\pi {{\varepsilon }_{0}}l}\]
D) \[-\frac{4{{q}^{2}}}{\sqrt{3}\pi {{\varepsilon }_{0}}l}\]
Correct Answer: D
Solution :
| Length of body diagonal \[=\sqrt{3}\ell \] |
| \[\therefore \] Distance of centre of cube from each corner \[r=\frac{\sqrt{3}}{2}\ell \] |
| P.E. at centre \[=8\times \] Potential Energy due to A \[=8\times \frac{Kq\times (-q)}{r}=8\times \frac{1}{4\pi {{\varepsilon }_{0}}\sqrt{3}\,l}\times 2\times q\times (-q)=\frac{-4{{q}^{2}}}{\sqrt{3}\,\pi {{\varepsilon }_{0}}l}\] |
You need to login to perform this action.
You will be redirected in
3 sec
