Fp=1 250-600=650 (H)
T=2ПИR/V
α=60 мю=0,9 а=?m*g*sin α - мю*m*g*cos α=m*a
a=g*(sin α - мю*cos α)=10*(0.866-0.9*0.5)=4.16 м/с^2
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k=<span>100Н/м</span>