Lightning bolts can carry currents up to approximately 20 ka. we can model such a current as the equivalent of a very long, straight wire. part aif you were unfortunate enough to be 4.5 m away from such a lightning bolt, how large a magnetic field would you experience? express your answer using two significant figures. b1 = t part bhow does this field (b1) compare to one (b2) you would experience by being 4.5 cm from a long, straight household current of 10 a? express your answer using two significant figures. b1/b2 =