同樣溫緊mid term的路過
1) F1 represents the force in each of the truss members
∑Fv = -100 + 2F1cos45 = 0
F1 = (100√2)/2
F1 = 70.7 N
2)差唔多
∑Fv = Fay + Fby - 50 = 0
tan50 = Fax / Fay .... (1)
tan70 = Fbx / Fby .... (2)
(1) / (2)
0.43 = 50 - Fay / Fay
1.43 Fay = 50
Fay = 34.87 N (As such Fby = 50 - 34.87 = 15.13N)
cos 50 = Fay / Fa
Fa = 54.25N
cos 70 = Fby / Fb
Fb = 44.24N
我啲phy還晒比先生, 所以粗粗地睇住先