你知唔知自己講緊乜野?
就算人類同外星人對何謂一日既定義有分別
亦只係單位唔同左
要形容既話就好似呎同厘米既關係
就算大家既量度單位唔同
但個實際長度都唔會因為咁而增加或者減少
另外科學家對一秒係有嚴格既物理定義
並唔係9up作出黎
Under the International System of Units, the second is currently defined as the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom.