1-3 할리데이 11판 솔루션 일반물리학

$$\ab{a}$$ $$ 1\ut{shake} = 10^{-8}\ut{s} $$ $$ \title{shake in second}$$ $$ \begin{aligned} 1\ut{s} &= 1\ut{s} \times \frac{1\ut{shake}}{10^{-8}\ut{s}}\\ &=10^8 \ut{shake} \end{aligned} $$ $$ \title{second in year}$$ $$ \begin{aligned} 1\ut{year} &= 1\ut{year}\times\frac{365\ut{day}}{1\ut{year}}\times\frac{24\ut{h}}{1\ut{day}}\times\frac{3600\ut{s}}{1\ut{h}}\\ &=365\times24\times3600\ut{s}\\ &=31536000\ut{s}\\ &=3.1536\times 10^7 \end{aligned} $$ $$ \title{shake in second > second in year} $$ $$\ab{b}$$ $$ \begin{cases} \text{HumanAge} &= 10^6\ut{years}\\ \text{UniverseAge} &= 10^{10}\ut{years} \end{cases} $$ $$ \text{HumanAge} : \text{UniverseAge} = x\ut{sec}:1\ut{day} $$ $$ \begin{aligned} \\ \Ans&=\frac{\text{HumanAge}\times1\ut{day}}{\text{UniverseAge}}\times\frac{24\ut{h}}{1\ut{day}}\times\frac{3600\ut{sec}}{1\ut{h}}\\ &=\frac{10^6\cdot24\cdot3600}{10^{10}}\ut{sec}\\ &=\frac{216}{25}\ut{sec}\\ &=8.64\ut{sec} \end{aligned} $$