Jawabanmu

2014-06-17T15:29:49+07:00
Dik : wu = 170 N ; wf = 150 maka Fa = wu-wf = 170-150 = 20 N
dit : Pb = ...?
jawab :  \frac{Pb}{Pf} =  \frac{w}{Fa}  \\ Pb =  \frac{w}{Fa}  x Pf \\ Pb =  \frac{170}{20}  x   10^{-3}   \\ maka Pb = 8 x  10^{-4}  :)