The magnetic flux linked with a coil, in webers, is given by the equations Φ = 3t² + 4t + 9. Then
the magnitude of induced e.m.f. at t = 2 second will be

The flux linked with a coil at any instant ‘t’ is given by Φ = 10t² – 50t + 250. The induced emf at t = 3 s is :

A coil having 500 square loops each of side 10 cm is placed normal to a magnetic flux which increases at the rate of 1.0 Tesla/second. The induced e.m.f. in volts is :