1-12 할리데이 11판 솔루션 일반물리학

$$ \rho = 1\ut{g/cm^3} $$ $$ \ab{a} $$ $$ \begin{aligned} m &= \rho V\\ &= 1\ut{g/cm^3} \cdot 1\ut{m^3}\\ &= \cfrac{1\ut{g}}{1\ut{cm^3}} \cdot \cfrac{1\ut{kg}}{1000\ut{g}}\cdot\(\cfrac{100\ut{cm}}{1\ut{m}}\)^3\cdot 1\ut{m^3} \\ &=\cfrac{100^3}{1000}\ut{kg}\\ &=1000\ut{kg} \end{aligned} $$ $$ \ab{b} $$ $$ \begin{aligned} \Ans&=\cfrac{4800\ut{m^3}}{15.7\ut{h}}\cdot\cfrac{1000\ut{kg}}{1\ut{m^3}}\cdot\cfrac{1\ut{h}}{3600\ut{sec}}\\ &=\cfrac{4800\cdot1000}{15.7\cdot3600}\ut{kg/s}\\ &=\cfrac{40000}{471}\ut{kg/s}\\ &\approx84.9256900212\ut{kg/s}\\ &\approx84.9\ut{kg/s}\\ &\approx85\ut{kg/s}\\ \end{aligned} $$

풀이자주 : (b)의 유효숫자가 모호하여 다양하게 표기했습니다.