1. | case (I) but not in case (II). |
2. | case (II) but not in case (I). |
3. | both cases (I) and (II). |
4. | neither of cases (I) and (II). |
The ratio of the radii of two circular coils is \(1:2.\) The ratio of currents in the respective coils such that the same magnetic moment is produced at the centre of each coil is:
1. \(4:1\)
2. \(2:1\)
3. \(1:2\)
4. \(1:4\)