Đáp án:
\(\begin{array}{l}
a.\\
\omega = 10\sqrt 5 rad/s\\
T = \dfrac{{\sqrt 5 \pi }}{{25}}s\\
f = \dfrac{{5\sqrt 5 }}{\pi }Hz\\
b.{\rm{W}} = 0,16J\\
c.{v_{\max }} = 0,8\sqrt 5 m/s
\end{array}\)
Giải thích các bước giải:
\(\begin{array}{l}
a.\\
\omega = \sqrt {\dfrac{k}{m}} = \sqrt {\dfrac{{50}}{{0,1}}} = 10\sqrt 5 rad/s\\
T = \dfrac{{2\pi }}{\omega } = \dfrac{{2\pi }}{{10\sqrt 5 }} = \dfrac{{\sqrt 5 \pi }}{{25}}s\\
f = \dfrac{1}{T} = \dfrac{1}{{\dfrac{{\sqrt 5 \pi }}{{25}}}} = \dfrac{{5\sqrt 5 }}{\pi }Hz\\
b.\\
L = 2A \Rightarrow A = \frac{L}{2} = \dfrac{{16}}{2} = 8cm\\
{\rm{W}} = \dfrac{1}{2}k{A^2} = \dfrac{1}{2}.50.0,{08^2} = 0,16J\\
c.\\
{v_{\max }} = \omega A = 10\sqrt 5 .0,08 = 0,8\sqrt 5 m/s
\end{array}\)