Предмет: Физика, автор: dasharumyantseva34

Ящик массой 80 кг равноускоренно поднимается с помощью троса вертикально вверх в течении 25 с на высоту 10 м. Определите силу напряжения троса.

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Ответы

Автор ответа: charger1337
4

Ответ:

Объяснение:

Нужно составить проекцию,опираюсь на второй закон Ньютона(F = ma) сил на ось y:

Fнатяжения направлена вертикально вврех , а Fтяжести вниз,движение равноускоренное значит есть ускорение следовательно уравнение будет таким:

Fнатяжения - Fтяжести = ma

мы не знаем значение ускорения надо его найти:

Ускорение:

a = \frac{2h}{t^{2} } = \frac{2*10}{25^{2} } = 0.032 м/с2

Fнатяжение - mg = ma

Fнатяжения = ma + mg

Fнатяжения = m(a+g)

Fнатяжения = 80*(0.032 + 9.8) =  786.56Н

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