JEE MainPhysicsElectromagnetic Induction
Three identical coils C₁ , C₂ and C₃ are fixed in space such that they share a common axis, with C₂ placed exactly midway between C₁ and C₃ . Coil C₁ carries an anti-clockwise current that is strictly decreasing with time, while coil C₃ carries a clockwise current that is strictly increasing with time. The induced current in coil C₂ will be
Options
- AAnti-clockwise
- BClockwise
- CZero
- DAlternating
Correct answer
A. Anti-clockwise
Step-by-step solution
Let the common axis of the coils be the z-axis, with the observer looking from the +z side towards the origin. Coil C₁ carries an anti-clockwise current, which produces a magnetic field in the +z direction at C₂ . Since this current is decreasing with time, the magnetic flux through C₂ in the +z direction is decreasing. This corresponds to a change in flux in the -z direction. Coil C₃ carries a clockwise current, which produces a magnetic field in the -z direction at C₂ . Since this current is increasing with time,