Two plane circular coilds P and Q have radii `r_(1)` and `r_(2)`, respectively,
Channel: Doubtnut
Date: 26/01/2020

Two plane circular coilds P and Q have radii `r_(1)` and `r_(2)`, respectively, `(r_(1) lt lt r_(2))` and are coaxial as shown in fig. The number of turns in P and Q are respectively `N_(1)` and `N_(2)`. If current in coil Q is varied steadily at a rate x ampere/second then the induced emf in the coil P will be approximatery -