9) P=m*g=5*10=50 H
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10) F1=2 H F2=12 H Lo=0.13 м x1=0.008 м L=?
k=F1/x1=F2/x2
x2=F2*x1/F1=12*0.008/2=0.048 м
L=Lo+x2=0.13+0.048=0.178 м
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11) P=50000 H po=13600 кг/м3 V=?
P=m*g=po*V*g
V=P/(po*g)=50000/(13600*10)=0.368 м3
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