Two identical current carrying coaxial loops, carry current I in an opposite sense. A simple amperian loop passes through both of them once. Calling the loop as C,
(a) ?Bdl =m $\propto$ I
(b) the value of  ?B.dl = ±2 $\propto$ I is independent of sense of C
(c) there may be a point on C where, B and dl are perpendicular
(d) B vanishes everywhere on C

There are two types of electricity - static and current. The current electricity is divided into Alternating Current (AC) and Direct Current (DC). Based on the production methods, electricity is divided into - heat, chemical, pressure, light and magnetism.

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