5-18 할리데이 11판 솔루션 일반물리학

$$ \begin{cases} g_1&=9.8\ut{m/s^2}\\ g_2&=6.0\ut{m/s^2}\\ g_3&=0\ut{m/s^2}\\ mg_1&=12\ut{N}\\ \end{cases} $$ $$m=\frac{12}{g_1},$$ $$\ab{a}$$ $$ \begin{aligned} mg_2&=\frac{12}{g_1}\cdot g_2\\ &=\frac{360}{49}\ut{N}\\ &\approx 7.346938775510204\ut{N}\\ &\approx 7.3\ut{N}\\ \end{aligned} $$ $$\ab{b}$$ $$ \begin{aligned} m&=\frac{12}{g_1},\\ &=\frac{60}{49}\ut{kg}\\ &\approx 1.224489795918367\ut{kg}\\ &\approx 1.2\ut{kg}\\ \end{aligned} $$ $$\ab{c}$$ $$ \begin{aligned} mg_3&=\frac{12}{g_1}\cdot 0\\ &=0\ut{N}\\ \end{aligned} $$ $$\ab{d}$$ $$ \begin{aligned} m&=\frac{12}{g_1},\\ &=\frac{60}{49}\ut{kg}\\ &\approx 1.224489795918367\ut{kg}\\ &\approx 1.2\ut{kg}\\ \end{aligned} $$