Answer to Question #257097 in Civil and Environmental Engineering for Nazmul

Question

1. Find the magnitude of two like parallel forces acting at a distance of 240 mm, whose resultant is 200 N, and its line of action is at a distance of 60 mm from one of the forces.?
2. ABCD is rectangle, in which AB = CD = 100 mm and BC = DA = 80 mm. Forces of 100 N each act along AB and CD and forces of 50 N each at along BC and DA. Find the resultant moment of the two couples.?
3. Two men carry a weight of 2 kN by means of two ropes fixed to the weight. One rope is inclined at 45° and the other at 30° with their vertices. Find the tension in each rope.

Answer 1

Skyli provides a workable method. I prefer a method easier to visualize:

2 x 100 x 40 N.mm+ 2 x 50 x 50 N.mm

= 13.0 newton.meters

as though the couple were acting through the centroid.

________________

given

• Weight of the block = W = 2 KN
• Angle of inclination of the first rope = 45
• Angle of inclination of the second rope =30

 

Let T1 and T2  be the tensions in the first and second rope respectively.

From the f.b.d. of the block

$T_1=1.36T_2$

$T_1=1.36\times1470=1794.11 N$