1-8 할리데이 11판 솔루션 일반물리학

$$\begin{cases} 1\ut{AU}&=1.50\times10^8\ut{km}\\ c&=3.0\times10^8\ut{m/s} \end{cases}$$ $$\begin{aligned} c&=\cfrac{3.0\times10^8\ut{m}}{1\ut{sec}}\times\cfrac{1\ut{km}}{1000\ut{m}}\times\cfrac{1\ut{AU}}{1.50\times10^8\ut{km}}\times\cfrac{3600\ut{sec}}{1\ut{h}}\\ &=\cfrac{3.0\cdot3600}{1000\cdot1.50}\ut{AU/h}\\ &=\cfrac{36}{5}\ut{AU/h}\\ &=7.2\ut{AU/h} \end{aligned}$$