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.
(a) If you were unfortunate enough to be 5.1 m away from such a lightning bolt, how large a magnetic field would you experience?
(b) How does this field compare to one you would experience by being 5.1 cm from a long, straight household current of 5 A?