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 =

Ibelieve the answer is b

Ohm's law tells you that i = v/r where v is equivalent voltage and r is equivalent resistance of the circuit
since all circuits have the same voltage, your question is really asking which circuit has the lowest total resistance, since the lower the resistance, the higher the current
circuit a has a resistance of 5 ohms; circuit c is in series so has a resistance of 10 ohms; circuit b is in parallel and therefore has a resistance of 2.5 ohms (review your notes on adding resistances in parallel and series); therefore b has the highest current

Answerigneous bedrock of the oceanic crust;