The Chief Examiner observed that this question was not popular among the candidates and the
few who attempted this question were reported not to have drawn the diagram correctly and this
also affected their performance. Candidates should represent the forces as indicated below
Using Lami's theorem, F/Sin 145° = 60/Sin 125° ⇒60xSin145°
Sin 125°
= 42.0N
Similarly, T = 60/125° =>T = 60Sin900
Sin90 Sin125°
= 73.2N
The solution could also be obtained by resolving the forces into its horizontal and vertical
components. In which case, we would obtain:
[0,-60] +[Fcos0,Fsin0] + [-Tcos55,Tsin55] = [0,0] i.e [0,-60] + [f,0] +[-0.5736T,0.8192T] = [0,0]