Dielectric moisture meters for rapid grain moisture determination operate on the principle that the dielectric constant of liquid water ($approx 80$) is:
Options:
(A) Substantially higher than that of bone-dry grain matter ($approx 3 - 5$)
(B) Identical to bone-dry grain matter
(C) Substantially lower than that of air ($approx 1$)
(D) Independent of excitation frequency
Answer Key:
A
Step-by-Step Solution & Explanation
The dielectric constant of water is $\approx 80$, whereas bone-dry biological grain tissue is only $3 - 5$. Hence, grain capacitance rises steeply with moisture content, enabling sensitive electrical moisture measurement.