Question

Two concentric coplanar coils of equal turns and radius 10 cm and 30 cm respectively as same current flowing in both are cause in same direction

Answer 1

Answer:

Two concentric coplanner coils of equal turns have radii 10 cm and 30 cm respectively. Same current flowin in both the coils in same direction. Now direction of current is reversed in one coil then ratio of magnetic fie at their common centre in two conditions respectively :- (1) 2:1 (2) 1:2 (3) 1:1 (4) 4 : 1.