(a) the coil is in a time-varying magnetic field.
(b) the coil moving in a time-varying magnetic field.
(c) the coil moving in a constant magnetic field.
An e .m.f is produced in a coil, which is not connected to anexternal voltage source. This can be due to (a) the coil is in a time-varying magnetic field. (b) the coil moving in a time-varying magnetic field. (c) the coil moving in a constant magnetic field. (d) the coil is stationary in an external spatially varying magnetic field, which does not change with time.
An e .m.f is produced in a coil, which is not connected to anexternal voltage source. This can be due to (a) the coil is in a time-varying magnetic field. (b) the coil moving in a time-varying magnetic field. (c) the coil moving in a constant magnetic field. (d) the coil is stationary in an external spatially varying magnetic field, which does not change with time.