If three infinite charged sheets of uniform surface charge densities `sigma, 2sigma` and `-4 sigma` are placed as shown in figure, then find out electric field intensities at points A, B, C and D.

Answer

`vec(E)_(A)=(-sigma)/(2 epsi_(0)) hat(j), vec(E)_(B)=(-3sigma)/(2 epsi_(0)) hat(j), vec(E)_(C)=(-7 sigma)/(2 epsi_(0)) hat(j), vec(E)_(D)=sigma/(2 epsi_(0)), hat(j)`