A biophysics experiment uses a very sensitive magnetic field

A biophysics experiment uses a very sensitive magnetic field probe to determine the current associated with a nerve impulse traveling along an axon.

Part A

If the peak field strength 1.1 mm from an axon is 9.0 pT , what is the peak current carried by the axon?

In Axon

B = u0*I/(2*pi*d)

i = B*2*pi*d/uo

i = 9.0*10^-12*2*3.14*1.1*10^-3/(4*3.14*10^-7) = 4.95*10^-8 Amp.

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