A.5m/s~10m/s B.10m/s~15m/s C.15m/s~20m/s D.5m/s~25m/s
A.螺母不動,螺桿回轉(zhuǎn)作直線運(yùn)動 B.螺桿不動,螺母回轉(zhuǎn)作直線運(yùn)動 C.螺桿回轉(zhuǎn),螺母作直線運(yùn)動 D.螺桿回轉(zhuǎn),螺母不動
A.2 B.1 C.1/2 D.3