2-6 할리데이 10판 솔루션 일반물리학

$$ \begin{cases} S &= 200\ut{m} \\ t &= 6.509\ut{s} \\ \Delta v &= 19\ut{km/h} \end{cases} $$ $$ \begin{aligned} & \\ \Ans &= t = ? \\&= \frac{S}{v} = \frac{S}{v_0+\Delta v} \\&= \frac{S}{\frac{S}{t}+\Delta v} \\&= \frac{200\ut{m}}{\frac{200\ut{m}}{6.509\ut{s}}+19\ut{km/h}\cdot \frac{1000\ut{m}}{1\ut{km}}\cdot \frac{1\ut{h}}{3600\ut{s}}} \\&= \frac{4686480}{843671}\ut{s} \\&\approx 5.5548667667846826547\ut{s} \\&\approx 5.6\ut{s} \end{aligned} $$