所屬欄目:機(jī)械安裝技術(shù)
(表1-40)表1-40國(guó)家選定的非國(guó)際單位制單位量的名稱單位名稱單位符號(hào)換算關(guān)系和說(shuō)明時(shí)間分[小]時(shí)天(日)minhd1min=60s1h=60min=3600s1d=24h=86400s平面角[角]秒[角]分度(″)(′)(°)1″=(π/648000)rad(π為圓周率)1′=60″=(π/10800)rad1°=60′=(π/180)rad旋轉(zhuǎn) ......(本文共 384 字 ) [閱讀本文] >>