5-42 할리데이 11판 솔루션 일반물리학

$$ \begin{cases} T_0&=43\ut{N}\\ v_a&=5.3\ut{m/s}\\ a_b&=1.2\ut{m/s^2}\\ v_b&=7.6\ut{m/s^2}\\ g&=9.80665\ut{m/s^2} \end{cases} $$ $$\ab{a}$$ $$\Sigma \vec F = 0 \Harr \Delta \vec v=0,$$ $$T_a=43\ut{N} $$ $$\ab{b}$$ $$\Sigma \vec F = m\vec a,$$ $$ \begin{cases} T_a-mg&=0\\ T_b-mg&=m(-a_b) \end{cases} $$ $$ \begin{aligned} T_b&=43-\frac{258}{5g}\\ &=37.7383\ut{N}\\ &\approx 38\ut{N} \end{aligned} $$