Four identical charges Q are fixed at the four corners of a square of side a find the electric field at a point p located symmetrycally at a distance of a by root two from the centre of the square

there r 4 charges at 4 corners of square...

so by the formula of electric field E=Q/4 pie r²ε₀ . put values in this formula and multiply it by 4.u will get answer

Regards

Arun (askIITians forum expert)