Вопрос школьника по предмету Физика
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К полюсам источника с ЭДС 2В и внутреним сопротивлением 0,8 Ом присоединен кусок никелиновой проволоки длиной 2,1М и сечением 0.21(мм в квадрате). Какого сопротивление на зажимах источника?
Ответ учителя по предмету Физика
U=I*R
R=pL/S=110*10^-8*2,1/0,21*10^-6=110*0,1=11Om
I=ε/R+r=2/11+0,8=0,16A
U=I*R=0,16*11=1,76=1,8B
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