Summary
The mechanical model allows students to explore seven aspects of electrical conduction in metals.
1 The de nition of electrical resistance R (the ratio V/I) and its dependence on the geometry (equations (1) and (2)).
2 Ohms Law (V/I constant if T constant) (equa tion (12)).
3 The temperature dependence of R via the temperature dependence of resistivity r (equation (13)).