1. A coil of self-inductance 0.04 H has a resistance of 15 Ω. Calculate the energy stored when it is connected to a 24 V d.c. supply.
2. The energy stored in the magnetic field of an inductor is 68 mJ, when it carries a current of 1.5 A. Calculate the value of self-inductance.
3. What value of current must flow through a 20 H inductor, if the energy stored in its magnetic field, under this condition, is 60 J?