Exercise 5 . Type the following command so that you will be able to see how the gradients are orthogonal to the contour lines . Show [ Contour Plot [ = [X , Y] , Ex, - 1 , 17, Ly, - 1 , 17, Contours - > 10] , VectorPlot [fix , Ey] , Ex, - 1 , 17 , Ey, - 1 , 17] , Plot Range - > A 1 1]