5555555555 12. An 18 V power supply is connected across a coil with a winding resistance of 180 . Current flow in the coil is ________. (a) 1 mA (b) 10 mA (c) 100 mA (d) 1 A
5555555555 17. The inductance of an iron-core coil decreases if ________. (a) the number of turns is decreased (b) the iron core is removed (c) the length of the coil decreases (d) none of the above
555555555522. What is the magnetomotive force in a 75-turn coil of wire when there are 4 A of current through it? (a) 18.75 At (b) 30 At (c) 300 At (d) 187 At