【上海科技英汉双解数学词典】俞竹君译上海科学技术.pdf
上海科技 英汉双解数学词典 俞竹君译 刘俊杰
abacus ancient calculating device madeOf a frame of paralll wires on whichbeadsarestrung The wires define place value(for example,in the decimalnumber sys-tem eachsuccessive wire,countingfromright toleft,would standfor u-nits,tens,hundreds,thousands,and sOn)and beads are slid to the topofeachw
acceleration3 travelling in a straight line accelerates at, for cxample,5 m s,its ve- locitymay be saidtobeinereasingby 5m severy second.The acceler ationofacarisusuallyjudgedbythetinrrakenbythecartoreach60 mph from zero.Thefewer the seconds thegreater the acceleration.