It is desired that a solenoid 37 cm long and with 410 turns produce a magnetic field within it equal to the Earth's magnetic field (5*10^-5 T). What current is required? Please show work and the answer, I want to see the steps in solving this problem. Thank you!
tigger
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I assume that you are asking about the magnetic flux density B inside the solenoid. The units of flux density are Tesla (T) while those of field (H) are amp/m.
You can use the equation B = u0*n*I where u0 is the permeability of free space (I assume that this is an air-cored coil), n is turns/metre , and I is current
I = B/(u0*n) = 0.37*5*10^-5/(410*1.257*10^-6) = 36mA