知識(shí)貝殼
知識(shí)貝殼
a lamp【問(wèn)】 The gas-filled tungsten filament lamp is more of a furnace than a lamp. Since it uses ninety per cent of the power to produce unwanted heat and uses only ten percent to makelight.[原譯]這種充氣鎢絲燈與其說(shuō)是一盞燈,不如說(shuō)是一個(gè)火爐。因?yàn)樗娜?0%的電能去 ......（本文共 840 字 ） [閱讀本文] >>