I=50 A L=0.08 м B=20*10^-3 Тл s=0.01 м A=?
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A=F*s=I*B*L*s=50*20*10^-3*0.08*0.01=0.8*10^-3 Дж (0,8 мДж)
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<span>r(t) = 3t·i + 2t·j + k
</span>|r(t)| = sqrt(9t^2 + 4t^2 +1)
|v(t)| = dr/dt = 13t / sqrt(13t^2 + 1)
|a(t)| = (dr/dt)^2 = (26(13t^2 + 1) - 13t) / (13t^2 + 1)^(3/2)
V=0,0005м3
р=1450кг/м3
m=pv
m=1450*0,0005=0,725кг=725г