1 \begin{problem*}{25.36}
2 An electric field in a region of space is parallel to the $x$ axis.
3 The electric potential varies with position as shown in Figure~P25.36.
4 Graph the $x$ component of the electric field versus position in this
10 size(6cm, 4cm, IgnoreAspect);
17 draw((0,0)--(1,Vmax)--(2,0)--(3,0)--(4,Vmin)--(5,0), red);
18 xaxis("$x$ (cm)", xmin=xmin, xmax=xmax, LeftTicks(NoZero));
19 yaxis("$V$ (V)", ymin=Vmin, ymax=Vmax, RightTicks);
25 $E_x=-\deriv{x}{V}$, so
30 size(6cm, 4cm, IgnoreAspect);
34 real Emin=-3e3; // 30V/1cm = 3kV/m
37 draw((0,Emin)--(1,Emin), red);
38 draw((1,Emax)--(2,Emax), red);
39 draw((2,0)--(3,0), red);
40 draw((3,Emax)--(4,Emax), red);
41 draw((4,Emin)--(5,Emin), red);
42 xaxis("$x$ (cm)", xmin=xmin, xmax=xmax, LeftTicks(NoZero));
43 yaxis("$E$ (V/m)", ymin=Emin, ymax=Emax, RightTicks);