i have a question i cant come up with the answer for. i have built a large solenoidal coil with # 8 awg magnet wire. i have wound 310 turns around an 8 inch length bobbin and have an iron core inside. the resistance is only .250 ohms for the entire coil. when i connect it to a 12 volt car battery nothing happens except a crackling noise at the battery. i connected it with the north pole to - and south pole to + . i also tried driving it with a pulse width modulator unit that is capable of 100 amps @12 volts and nothing happened, no magnetic field and the coil doesnt even get warm. my questions are: is 12 volts not enough to push the current through the wire even though it has a very low resistance and if so, how much voltage would it take to push 50 amps through the coil?