11판/8. 퍼텐셜에너지와 에너지 보존

8-82 할리데이 11판 솔루션 일반물리학

짱세디럭스 2024. 4. 12. 19:27
$$ \begin{cases} F&=750\ut{N}\\ k&=2.5\times10^5\ut{N/m}\\ \end{cases} $$ $$\ab{a}$$ $$F=kx,$$ $$ \begin{aligned} x&=\frac{F}{k}\\ &=3.0\times10^{-3}\ut{m}\\ &=3.0\ut{mm}\\ \end{aligned} $$ $$\ab{b}$$ $$ \begin{aligned} W&=\frac{1}{2}kx^2\\ &=\frac{1}{2}k\(\frac{F}{k}\)^2\\ &=\frac{F^2}{2k}\\ &=\frac{9}{8}\ut{J}\\ &=1.125\ut{J}\\ &\approx 1.1\ut{J} \end{aligned} $$ $$\ab{c}$$ $$F=kx,$$
$$\ab{d}$$ $$F=\frac{1}{2}kx^2,$$
$$\ab{e,f}$$ (풀이자 주 : 그래프가 직선은 아니지만, 직선으로 근사하여 풀겠습니다.) $$ \begin{aligned} F&=kx\\ 6000\ut{N}&=k\cdot10\ut{mm},\\ k&=6\times10^5\ut{N/m} \end{aligned} $$ $$\ab{e}$$ $$ \begin{aligned} W&=\frac{1}{2}kx^2\\ &=\frac{363}{10}\ut{J}\\ &=36.3\ut{J}\\ \end{aligned} $$ $$\ab{f}$$ $$\text{Exist}$$