question_answer

Equal charges q are placed at the four corners A, B, C, D of a square of side a. The magnitude of the force on the charge at C will be

A)  \[\frac{3{{q}^{2}}}{4\pi {{\varepsilon }_{0}}{{a}^{2}}}\]                 

B)  \[\frac{4{{q}^{2}}}{4\pi {{\varepsilon }_{0}}{{a}^{2}}}\]

C)  \[\left( \frac{1+2\sqrt{2}}{2} \right)\frac{{{q}^{2}}}{2\pi {{\varepsilon }_{0}}{{a}^{2}}}\]

D)  \[\left( 2+\frac{1}{\sqrt{2}} \right)\frac{{{q}^{2}}}{4\pi {{\varepsilon }_{0}}{{a}^{2}}}\]

Correct Answer: C

Solution :

 \[2HCO{{O}^{\bullet }}\xrightarrow{\,}\,{{H}_{2}}+2C{{O}_{2}}\] \[2{{H}_{2}}O+2{{e}^{-}}\xrightarrow{\,}\,{{H}_{2}}+2O{{H}^{\odot -}}\]