2-39 할리데이 10판 솔루션 일반물리학

$$\begin{cases} t_0= & \text{Car Bike Meet} \\ t_1= & \text{Bike Start} \\ t_2= & \text{Car Bike Meet Again} \\ \end{cases}$$ $$\begin{cases} v_C= 46\ut{m/s} \\ t_1= 1.0\ut{s} \\ a_B= 4.0\ut{m/s^2} \\ \Delta x_{C0\to 2} = \Delta x_{B1\to 2} = S \\ \end{cases}$$ $$t_2 =?$$ $$\begin{aligned} \Delta x&=vt, \\ \Delta x_{C0\to2}&=v_Ct_{0\to2}, \\ S&=v_C(t_2-t_0)\cdots(2-39-1)\\ \end{aligned} $$ $$ \begin{aligned} \Delta x&=v_0t+\frac{1}{2}at^2,\\ \Delta x_{B1\to2} &=v_1t_{1\to2} +\frac{1}{2}a_Bt_{1\to2}^2\\ S&=\frac{1}{2}a_B(t_2-t_1)^2\cdots(2-39-2) \end{aligned}$$ $$(2-39-1),(2-39-2),$$ $$\text{(Make System of Equations)}$$ $$\text{(Underset x,y Means Unknown Value)}$$ $$\begin{cases} \underset{x}{S}=v_C(\underset{y}{t_2}-t_0) \\ \underset{x}{S}=\frac{1}{2}a_B(\underset{y}{t_2}-t_1)^2 \\ \end{cases}$$ $$\begin{aligned} t_2 &= \frac{2 v_C}{a_B}+t_1 \\ &= \frac{2 (46\ut{m/s})}{4.0\ut{m/s^2}}+1.0\ut{s} \\ &= 24\ut{s} \end{aligned}$$