12.04.2022

диаметр колеса вагона метрополитена равен 78см. за 2,5 мин колесо делает 1000 оборотов. найдите скорость поезда в метро в км/ч. ответ округлите до десятых

Ответ учителя по предмету Математика

Получилось как-то так)

3,14*0,78*0,78=1,91 м — длина пути пройденного за 1 оборот

2,5 мин=150 с

1000/150=200/30=20/3

1,91*20/3=12,7 м/с

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