In soil conditions, a dry, sandy, loosely packed soil provides which characteristic?

• A. low resistivity and strong conduction
• B. medium resistivity and good conduction
• C. high resistivity and poor conductive atmosphere
• D. very low resistance and strong conduction

Answer: (C)

Resistivity is the measure of how strongly a material resists the flow of electrical current. In soils, moisture and texture govern this. Water and dissolved ions carry charge, so when soil is moist, resistivity drops and conduction improves. Dry, sandy, loosely packed soil has little water and many air spaces, leaving few pathways for ions to move. That makes the soil resist current more strongly, i.e., it has high resistivity and a poor conductive environment. If the soil were wetter or finer, resistivity would be lower and conduction better, which is the opposite situation.