This diagram illustrates how heat at temperature T1 at one end of an object (looking at cross-sectional area A and length L) reaches the other end at temperature T2 by conduction. When the cross-sectional area of the object is increased or the length is shortened, the thermal resistance of the conductor decreases. The equation to determine (T1 - T2) consequently becomes the thermal resistance (Rth) times the heat flow (P), in keeping with the “Thermal Ohm’s Law”. To decrease the thermal resistance: increase the cross section of the object, decrease the length of the object, or select material with a higher thermal conductivity.