Case I- represents two concentric spheres of inner radius a and outer radius `b`. The volume between two sphere is filled with a material of electric conductivity `sigma` dielectric constant `k`.
Case II -represents two coaxial long cylindrical shells of inner radius a and outer radius `b`, each having length `l(lgt gt a,b)`. The volume between two cylindrical shells is filled with a material of electrical conductivity `sigma` and dielectric constant `k`.

The inner sphere in case I and inner cylinder in case II is given a charge `+q` each and the outer sphere in case I and outer cylinder in case II is given a charge `-q` each. Which of the following statement(s) are CORRECT?

Options

A. charge in both the cases decays exponentially with time
B. time constant of charge decay is same in both the case.
C. current in both the cases is same at all instants
D. heat loss is same in both the cases