A body weighing 13 kg is suspended by two strings 5 m and 12 m long, their other ends being fastened to the extremities of a rod 13 m long. If the rod be so held that the body hangs immediately below the middle point, then the tensions in the strings are:
Solutions · 1
Official solution
Since 132=52+122, the triangle formed by the strings and the rod is right-angled at the point C where the strings meet. By Lami's theorem at C:
\[T_1=13\sin\theta = 13\cdot\frac5{13}=5\text{ kg},\qquad T_2=13\cos\theta = 13\cdot\frac{12}{13}=12\text{ kg}\]