Sorry, 算錯了, 差一個 order.活塞半徑=2cm, 面積=1.256x10^(-3) m^21 Bar = 10^5 N/m^2,9 Bar = 9 x 10^5 = F/1.256x10^(-3)F = 1130 N = 113 kg,F/9 = 12.5 kg