The given situation is shown below.
According to given situation we have to find electric field at point
P(0,0,1).
Distance of point
P from each charges is equal to
√12+12=√2 EAP=EBP=ECP=EDP=⋅=⋅ EAP and
EBP are perpendicular to each other. Let
E′ be the resultant electric field of
EAP and
EBP, then
E′=√EAP2+EBP2=√2EAP2.[∵EAP=EBP]=EAP√2==E′= In the similar way, net electric field due to
ECP and
EppE′′=⋅ Again
E′ and
E′′ are directed in same direction i.e along
+z direction, hence net electric field,
Enet =E′+E′′=2E′[∵E′=E′′] =2=N∕C
