6-3 할리데이 11판 솔루션 일반물리학

$$ \begin{cases} m_t&=5.00\ut{kg}\\ m_b&=6.00\ut{kg}\\ M&=m_t+m_b=11.00\ut{kg}\\ F_{t\min}&=25\ut{N} \end{cases} $$ $$ \begin{aligned} f_s&=\mu_sF_N,\\ 25&=\mu_s\cdot (5\cdot g)\\ \mu_s&=\frac{5}{g}\\ \end{aligned} $$ $$\Sigma \vec F = m\vec a,$$ $$a=\frac{F}{m_t+m_b}=\frac{F}{M}\\$$ $$\ab{a}$$ $$ \begin{aligned} \Sigma F_t&=m_ta\\ \mu_sF_N&=m_t\frac{F}{M}\\ \mu_sm_tg&=m_t\frac{F}{M}\\ \end{aligned} $$ $$ \begin{aligned} F&=\mu_sMg\\ &=\frac{5}{g}Mg\\ &=5M\\ &=55.0\ut{N} \end{aligned} $$ $$\ab{b}$$ $$ \begin{aligned} a&=\frac{F}{m_t+m_b}=\frac{F}{M}\\ &=\frac{5M}{M}\\ &=5.00\ut{m/s^2}\\ \end{aligned} $$