12. The resistivity of a semiconductor can be modified by adding different amounts of impurities. A rod of semiconducting material of length L and cross-sectional area A lies along the x-axis between x=0 and x=L. The material obeys Ohm's law, and its resistivity varies along the rod according to p(x) = PooExp(-x/L)The end of the rod at is at a potential greater than the end at x=0 is at a potential Vo greater than the end x=L. (a) Find the total resistance of the rod and the current in the rod. (b) Find the electric-field magnitude in the rod as a function of x. (c) Find the electric potential in the rod as a function of x. (d) Graph the functionsp(x), E (x) and V(x), for values of x between x = 0 and x = L

12. The resistivity of a semiconductor can be modified by adding different amounts of impurities. A rod of semiconducting material of length L and cross-sectional area A lies along the x-axis between x=0 and x=L. The material obeys Ohm's law, and its resistivity varies along the rod according to p(x) = PooExp(-x/L)The end of the rod at is at a potential greater than the end at x=0 is at a potential Vo greater than the end x=L. (a) Find the total resistance of the rod and the current in the rod. (b) Find the electric-field magnitude in the rod as a function of x. (c) Find the electric potential in the rod as a function of x. (d) Graph the functionsp(x), E (x) and V(x), for values of x between x = 0 and x = L