Answer to Question #61361 in Electricity and Magnetism for bebeji

Question

7 )A coil of inductance 2.0H and resistance 5Ê is connected to a 30V battery. Calculate the rate of current growth in the coil when the circuit has just been made and when the current reaches one-half of its steady-state vaule.
a)15A/s and 7.5A/s
b) 3.5A/s and 10A/s
c) 12A/s and 4.4A/s
d) 6.2A/s and 18A/s
8) A 1000-turns coil of cross-sectional area 30cm2 rotates at a frequency of 120 Hz in a magnetic field 0.1 T. Calculate the peak value of the induced emf
a) 346.4V
b) 112.3V
c) 97.6V
d) 226.2V