Question

The truss is made from five members, each having a length of 4 m and a mass of 7 kg/m. If the mass of the gusset plates at the joints and the thickness of the members can be neglected, determine the distance d to where the hoisting cable must be attached, so that the truss does not tip (rotate) when it is lifted.

Answer 1

Answer:

the distance d to where the hoisting cable must be attached, so that the truss does not tip (rotate) when it is lifted will be 3m

Explanation:

In this question we have given,

Length of each member of truss= 4m

Mass if each member of truss= 7kg/m

and number of member in truss=5

Therefore,

$\sum xM=4\times 7(1+2+3+4=5)\\\sum xM=420 kgm$

$\sum M=4\times 7\times 5\\\sum M=140kg$

Therefore, the distance d to where the hoisting cable must be attached, so that the truss does not tip (rotate) when it is lifted will be

$d=\frac{\sum xM}{\sum M} \\d=\frac{420kgm}{420kg} \\d=3m$