E=21 R1=R2=R3=3 R4=6 r=1 Io=?
R23=3*3/(3+3)=1.5 Ом
R234=1.5*6/(1.5+6)=1.2 Ом
Ro=R1+R234=3+1.2=4.2 Ом
Io=E/(Ro+r)=21/(4.2+1)=4 A
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Дано:
F=250H
∆l=0,4см
F2=500H
k=k2
g≈10H/кг
∆l2=?
∆l2=F2/k*m
k=F/∆l*m
m=F/g
∆l2=F2/(F/((∆l*(F/g))*F2/g)
∆l2=500/(250/(0,4*(250/10)))*500/10=500/((0,4*25)*50)=500/(10*50)=1см
Q=40*10^-9 Кл F=40 H E=?
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E=F/q=40/(40*10^-9)=10^9 Н/Кл
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