M=0.02 кг R=0.25 м T=0.2 c V=? F=?
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V=2*π*R/T=2*3.14*0.25/0.2=7.85 м/с
F=m*V²/R=0.02*7.85²/0.25≈4.93 H (≈5 H)
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Vсм=весь путь/все время=S/((S/(4*1,5V))+((3/4S)/V)))=12,
1/(2/(4*3V)+(3*3/(4*3*V))=12,( 11/12V)*12=1, 11/V=1, V=11м/с