2-11 할리데이 10판 솔루션 일반물리학

$$ \begin{cases} v_c &= 15.00\ut{m/s} \\ t &= 150.0\ut{s} \\ x_{c0}-x_{a0} &= 1.500\ut{km} \end{cases} $$ $$ \begin{aligned} \Ans &= v_a = ? \\ x_{c0}+\Delta x_c &= x_{a0}+\Delta x_a \\ x_{c0}-x_{a0} &= \Delta x_a-\Delta x_c \\ &= v_at-v_ct \\ &= (v_a-v_c)t \\ v_a-v_c&= \frac{x_{c0}-x_{a0}}{t} \\ v_a&= \frac{x_{c0}-x_{a0}}{t}+v_c \\ &= \frac{1.500\ut{km}}{150.0\ut{s}}\cdot\frac{1000\ut{m}}{1\ut{km}}+15.00\ut{m/s} \\ &= 25\ut{m/s} \end{aligned} $$