2-17 할리데이 11판 솔루션 일반물리학

12-23 할리데이 11판 솔루션 일반물리학 $$\begin{cases} \text{A : Car}\\ \text{B : Truck} \end{cases}$$ $$\begin{cases} a_A&=1.80\ut{m/s^2}\\ v_{A0}&=0\\ v_B&=7.30\ut{m/s} \end{cases}$$ $$\ab{a}$$ $$S=v_0t+\frac{1}{2}at^2,$$ $$\begin{aligned} S&=v_0t+\frac{1}{2}at^2\\ v_Bt&=(0)t+\frac{1}{2}(a_A)t^2\\ \(7.30\ut{m/s}\)&=\frac{1}{2}\(1.80\ut{m/s^2}\)t\\ \end{aligned}$$ $$t=\frac{73}{9}\ut{s}$$ $$\begin{aligned} S &= vt\\ &=\(7.30\ut{m/s}\)\cdot\(\frac{73}{9}\ut{s}\)\\ &=\frac{5329}{90}\ut{m}\\ &\approx59.21111111111111\ut{m}\\ &\approx59.2\ut{m}\\ \end{aligned}$$ $$\ab{b}$$ $$v=v_0+at,$$ $$\begin{aligned} v&=(0)+\(1.80\ut{m/s^2}\)\(\frac{73}{9}\ut{s}\)\\ &=\frac{73}{5}\ut{m/s}\\ &=14.6\ut{m/s}\\ \end{aligned}$$