L=0.2 м a=0.05 м b=0.15 м I1=120 A I2=30 A μo=4*π*10^-7 Гн/м
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1) B1=μo*I1/(2*π*(L/2))=μo*I1/(π*L)
B2=μo*I2/(π*L)
B=B1-B2=μo*(I1-I2)/(π*L)=4*π*10^-7*(120-30)/(π*0.2)=1.8*10^-4 Тл
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2) B=μo*(I1/(L-b) - I2/(L-a)/(2*π)=2*10^-7*(120/(0.2-0.15) - 30/(0.2-0.05))=4.4*10^4 Тл
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