9-8 할리데이 11판 솔루션 일반물리학

$$\begin{cases} m&=2900\ut{kg}\\ v&=175\ut{m/s}\\ \Delta m&=920\ut{kg}\\ \end{cases}$$ $$\Delta \Sigma \vec P=0,$$ $$\begin{aligned} m_iv_i&=m_fv_f\\ v_f&=\frac{m_i}{m_f}v_i\\ &=\frac{25375}{191}\ut{m/s}\\ &\approx 132.85340314136127\ut{m/s}\\ &\approx 133\ut{m/s}\\ &\approx 1.3\times10^2\ut{m/s}\\ \end{aligned}$$