Предмет: Физика, автор: kristya1211

Тепловоз по горизонтальном участке пути длинной 600 м развивает постоянную силу тяги 147кН. Скорость поезда возрастает при этом от 36 до 54 км/ч. Определите силу сопротивления движению,считая ее постоянной. Масса поезда 1000 т.

Ответы

Автор ответа: vajny

0

v1 = 10 м/с, v2 = 15 м/с.

Перемещение:

$S=frac{v_{2}^2-v_{1}^2}{2a},$

Отсюда ускорение:

$a=frac{v_{2}^2-v_{1}^2}{2S}=frac{225-100}{1200}=0,1 m/c^2.$

По 2 закону Ньютона:

Fтяги - Fcопр = ma

Fсопр = Fтяги - ma = 147 кН - 100 кН = 47 кН.

Ответ: 47 кН.

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Task 1:
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Task
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− uses a variety of linking words;
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