A.R/2 B.R/8 C.R/16 D.16R
A.只與流經(jīng)管道的長(zhǎng)度成正比 B.與流速和管長(zhǎng)的乘積成正比 C.為0 D.條件不足,無(wú)法確定
A.9.8Pa B.9800Pa C.109800Pa D.90200Pa