Two concentric circular loops of radii` r_(1)` and `r_(2)` carry clockwise and anticlockwise currents `i_(1)` and `i_(2)`. If the centre is a null point, `i_(1)//i_(2)` must be equal to

Two concentric coplanar circular loops of radii r_(1) and r_(2) carry currents of respectively i_(1) and i_(2) in opposite direction (one clockwise and the other anticlockwise). The magnetic induction at the centre of the loops is half that due to i_(1) alone at the centre. if r_(2)=2r_(1) . the value of i_(2)//i_(1) is

Two concentric coplanar circular loops of radii r_(1) and r_(2) carry currents of respectively i_(1) and i_(2) in opposite direction (one clockwise and the other anticlockwise). The magnetic induction at the centre of the loops is half that due to i_(1) alone at the centre. if r_(2)=2r_(1) . the value of i_(2)//i_(1) is

Two coaxial circular loops of raadii r_(1) and r_(2) are separated by a distance x and carry currents i_(1) and i_(2) respectively. Calculate the mutual inductance. What is the force between the loops ?

Two concentric circular coils of radii R and r (lt lt R) carry currents of i_(1) and i_(2) respectively. If the smaller coil is rotated slightly about one of its diameter, it starts oscillating. Then, which of the following statement(s) is//are correct ?

Two concentric circular coils of radii R and r (lt lt R) carry currents of i_(1) and i_(2) respectively. If the smaller coil is rotated slightly about one of its diameter, it starts oscillating. Then, which of the following statement(s) is//are correct ?

Two circular loops A and B of radii R and 4R are kept concentrically in the same plane. The loops carry currents I_(1) and I_(2) respectively. If the magnetic field at a point on the common axis of the loops at a distance 2R from their common centre is zero, the ratio (I_(1))/(I_(2)) is _________.

A and B are two concentric circular conductors of centre O and carrying currents i_(1) and i_(2) as shown in the adjacent figure. If ratio of their radii is 1:2 and ratio of the flux densities at O due to A and B is 1:3 , then the value of i_(1)//i_(2) is