솔루션피아

$$ \begin{cases} k&=200\ut{N/m}\\ mg&=20\ut{N}\\ g&=9.80665\ut{m/s^2} \end{cases} $$ $$ \put \begin{cases} \KE : \text{Kinetic Energy}\\ \GE : \text{Gravitational Potential Energy}\\ \LE : \text{Elastic Potential Energy}\\ \end{cases} $$ $$ \begin{aligned} \Delta \GE(y_f)&=\Delta(mgy)\\ &=mg \Delta y\\ &=mg (y_f-y_i)\\ &=mg y_f\\ &=20 y_f\taag 1\\ \end{aligned} $$ $$\Delta x=-\Delta y$$ $$x_f=-y..

$$ \begin{cases} \frac{m}{t}&=5.5\times10^6\ut{kg}\\ \Delta y&=-50\ut{m}\\ g&=9.80665\ut{m/s^2}\\ \rho&=1000\ut{kg/m^3}\\ p&=10\ut{₩/kW\cdot h}\\ \end{cases} $$ $$ \put \begin{cases} \GE : \text{Gravitational Potential Energy}\\ \EE : \text{Electric Energy} \end{cases} $$ $$\ab{a}$$ $$ \begin{aligned} \frac{\Delta \GE}{t}&=\frac{\Delta (mgy)}{t}\\ &=\frac{mg\Delta y}{t}\\ &=\frac{m}{t}g\Delta y\..

$$ \begin{cases} mg&=12000\ut{N}\\ F_1&=500+1.8v^2\\ v&=70\ut{km/h}=\frac{175}{9}\ut{m/s}\\ a&=0.92\ut{m/s^2}\\ 1\ut{hp}&=75\ut{kgf\cdot m/s}=75g\ut{W}\\ g&=9.80665\ut{m/s^2}\\ \end{cases} $$ $$\Sigma F = ma,$$ $$F_2-F_1=ma$$ $$ \begin{aligned} F_2&=F_1+ma\\ \end{aligned} $$ $$ \begin{aligned} P&=F_2\cdot v\\ &= (F_1+ma)\cdot v\\ &= (500+1.8v^2+ma)\cdot v\\ &=\frac{875 (2125 g+19872)}{81 g}\ut{W..

$$ \begin{cases} m&=1.88\ut{kg}\\ \theta&=34.0\degree\\ v_0&=24.0\ut{m/s}\\ g&=9.80665\ut{m/s^2} \end{cases} $$ $$ \put \begin{cases} \KE : \text{Kinetic Energy}\\ \GE : \text{Gravitational Potential Energy}\\ \end{cases} $$ $$\ab{a}$$ $$ \begin{aligned} \KE&=\frac{1}{2}m{v}^2,\\ &=\frac{13536}{25}\ut{J}\\ &=541.44\ut{J}\\ &\approx 541\ut{J}\\ \end{aligned} $$ $$\ab{b}$$ $$v_f=v_x=v\cos\theta$$ ..

$$ \begin{cases} mg&=620\ut{N}\\ v_0&=0\\ a&=\Cons\\ \Delta S&=6.5\ut{m}\\ \Delta t&=1.6\ut{s}\\ \end{cases} $$ $$\ab{a}$$ $$S=\frac{1}{2}\(v+v_0\)t,$$ $$ \begin{aligned} v&=\frac{2S}{t}-v_0\\ &=\frac{2S}{t}\\ &=\frac{65}{8}\ut{m/s}\\ &=8.125\ut{m/s}\\ &\approx 8.1\ut{m/s}\\ \end{aligned} $$ $$\ab{b}$$ $$\KE=\frac{1}{2}mv^2,$$ $$ \begin{aligned} \KE&=\frac{1}{2}m\(\frac{2S}{t}\)^2\\ &=\frac{2mS^..

$$ \begin{cases} m&=6.20\ut{kg}\\ \theta&=30.0\degree\\ v_0&=6.00\ut{m/s}\\ g&=9.80665\ut{m/s^2}\\ \end{cases} $$ $$ \put \begin{cases} \KE : \text{Kinetic Energy}\\ \GE : \text{Gravitational Potential Energy}\\ \TE : \text{Thermal Energy}\\ \end{cases} $$ $$ \sin\theta=\frac{\Delta h}{\Delta S} $$ $$ \begin{aligned} \Sigma F_y=N-mg\cos\theta=0 \end{aligned} $$ $$\Sigma \Delta E=0,$$ $$\Delta \K..

$$ \put \begin{cases} U : \text{Potential Energy}\\ \end{cases} $$ $$ \begin{cases} U_A&=60\ut{J}\\ W_{A\rarr B}&=+35\ut{J} \end{cases} $$ $$W_{i\rarr f}=-\Delta U_{i\rarr f},$$ $$U_A-U_B=W_{A\rarr B}$$ $$ \begin{aligned} U_B&=U_A-W_{A\rarr B}\\ &=60-(+35)\\ &=25\ut{J} \end{aligned} $$

$$ \begin{cases} m&=0.50\ut{kg}\\ v_i&=13\ut{m/s}\\ h_{\max}&=7.0\ut{m}\\ g&=9.80665\ut{m/s^2}\\ \end{cases} $$ $$ \put \begin{cases} \KE : \text{Kinetic Energy}\\ \GE : \text{Gravitational Potential Energy}\\ \ME : \text{Mechanical Energy}\\ \end{cases} $$ $$ \begin{aligned} \Delta \ME &= \Delta (\KE+\GE)\\ &=\Delta \KE+\Delta \GE\\ &=\Delta \(\frac{1}{2}mv^2\)+\Delta (mgh)\\ &=\frac{1}{2}m\Del..

$$ \put \begin{cases} \KE : \text{Kinetic Energy}\\ \GE : \text{Gravitational Potential Energy}\\ \LE : \text{Elastic Potential Energy}\\ \end{cases} $$ $$ \begin{cases} k&=620\ut{N/m}\\ x_i&=25\ut{cm}=0.25\ut{m}\\ mg&=50\ut{N}\\ v_i&=0\\ \GE(0)&=0\\ \end{cases} $$ $$ \begin{aligned} \Delta x &= -\Delta h\\ x_f-x_i&=h_i-h_f\\ x_f&=x_i-h_f\\ \end{aligned} $$ $$\Sigma \Delta E=0,$$ $$\Delta \KE+\D..

(풀이자 주 : 주어진 U함수가 그래프로만 주어져 있습니다. 문제의 의도가 눈대중으로 풀라는 것으로 보입니다만, 풀이자가 임의로 그래프가 흡사한 함수를 추정하여 풀었습니다.) $$ \begin{aligned} \put &U(r\ut{nm})\\ &=\frac{87500 }{17}r^5-\frac{108750 }{17}r^4+\frac{42625 }{17}r^3\\ &~~~~~~-\frac{7425}{34}r^2-50 r+\frac{179}{34}\ut{\times 10^{-19}~J} \end{aligned} $$ $$\ab{a}$$ $$\Sigma E =E_a\gt 0,$$ $$ \put r_1\begin{cases} U(r_1)=E_a\\ 0\lt r_1\lt0.2\ut{nm} \end{cases} ..