7-44 할리데이 11판 솔루션 일반물리학

$$ \begin{cases} m_A&=5700\ut{kg}\\ m_B&=2020\ut{kg}\\ v&=2.0\ut{m/s}\\ g&=9.80665\ut{m/s^2}\\ \end{cases} $$ $$P=\vec F \cdot \vec v,$$ $$ \begin{aligned} P&=\Sigma m gv\\ &=15440g\\ &=151414.676\ut{W}\\ &\approx 1.5\times10^5\ut{W}\\ &\approx 0.15\ut{MW} \end{aligned} $$