Предмет: Физика, автор: iLogan

1.     Уравнение гармонического колебания материальной точки
массой m=10 г имеет вид s=2cos(150t+0,5). Определить полную энергию материальной точки и
действующую на нее максимальную возвращающую силу.







2.     Для того чтобы растянуть пружину на 2 см, необходимо
приложить силу 40 Н. Какая работа совершается при сжатии пружины на 5 см?





Ответы

Автор ответа: alecop
0
1. Полная энергия = кинетической энергии в точке равновесия, в которой скорость максимальна
v(t)=s'(t)=-300sin(...)
vmax=300
E=m*vmax^2/2=0.01*300^2/2=450 Дж

a(t)=v'(t)=-45000cos(...)
amax=45000
Fmax=m*amax=450 Н

2. F=kx
k=F1/x1
F2=k*x2=F1*x2/x1=40*5/2=100 H
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