Electromagnetic Field Theory - Engineering

Q1:

In a conductor which of the following relations hold good?

A ∇ x D = r

B ∇ . D = r

C ∇ x D = 0

D ∇ . D = 0

ANS:C - ∇ x D = 0

Inside a conductor free charge is zero, hence, ∇ x D = 0.