?外引力场
外引力场
地物 地球外部引力场
The coil is suspended in an external magnetic field and the current running through it adjusted so that the attraction between the two magnets balances the gravitational force on the suspended mass.
ECONOMIST: Weighing a kilogram
英汉双解词典包含3185865条英汉词条,基本涵盖了全部常用单词的翻译及用法,是英语学习的有利工具。