4. A 2-pole DC generator has an armature containing a total of 40 conductors connected in two parallel paths. The flux per pole is 6.48 x 10 lines and the speed of the prime mover is 30 rpm. The resistance of each conductor is 0.01 ohm and the current carrying capacity of each conductor is 10 A. Calculate the terminal voltage of the generator. 5. A magnetic ring with a mean diameter of 25 cm and a cross-sectional area of 5 square cm is wound with a coil of 600 turns. An air gap of 4 mm is made by cutting a section of the ring. A current of 10 A is passed through the coil. Determine the energy stored in the air gap. Assume relative permittivity of the ring to be 1000. (W-energy-B²V/2H)