Seawater at a frequency
f=9×102Hz, has permittivity
ε=80ε0 and resistivity
r=0.25Ω−m. Imagine a parallel plate capacitor is immersed in seawater and is driven by an alternating voltage source
V(t)=V0sin(2πft). Then, the conduction current density becomes
10x times the displacement current density after time
t=s. The value of
x is ..............
( Take ,=9×109N−m2C−2)