Предмет: Физика, автор: arthursushko

1.Шайба,пущена по поверхности ледяного стадиона,останавливается через 8с после удара.Какой была начальная скорость движения шайбы,если коэффициент трения скольжения равен 0,05?

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Ответы

Автор ответа: yuravasilchiko1

0

В формулу v=v0-at подставляем v=0, v0=8, получаем: at=8(м/с)
В формулу s=v0*t-at*t/2 подставляем данные: 64=8t-8t/2,
отсюда время: t=64/4=16 (с) и ускорение: a=8/16=1/2 (м/сс) .
Сила трения: k*mg=ma, отсюда k=a/g=0,5 / 10=0,05.

arthursushko: Тут нашёл коэффициент трения,а нужна начальная скорость!

arthursushko: Парень,помоги

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