Предмет: Физика, автор: кристинка199914

лощадь равномерно везет сани массой 300кг сила трения составляет 0,1 от веса саней с какой скоростью движется лошадь если за 1 час работа по перемещению саней составляет 2,1 МДЖ?

Ответы

Автор ответа: nastyawolk

F тр=0.1*P=0.1*10*300=300 Н
A=F*S отсюда S=A/F=2.1*10^6/300=7000 м
т.к равномерное движение ускорение равно 0, значит находим V из формулы
S=V*t отсюда V=S/t=70003600 (cек) = 1.9 м/с примерно 2 м/с
Ответ: 2 м/с.

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