9.4 Example 4

Calculate the resultant, at joint O, of the applied forces.

Solution with FisicaLab

Select the group Static and, inside this, the module Static of solids. Erase the content of the chalkboard and select the SI system. And add one element Stationary reference system, one element Beam, three elements of beam and the necessary elements Force and Resultant, as show the image below:

The gravity value is added to default. Now to the element Beam, that we call Beam, we have:

Name

Beam

m

0

lc

0

ang

55

To the element of beam that represent the lower side, and to the resultant applied here, we have:

Name

Beam

l

0

M

Mr

f

Fr

ang

angr

On the resultant element all are unknown data. Now to the element of beam that represent the point A, and to the applied force, we have:

Name

Name

l

62 @ cm

f

50

ang

15

To the element of beam that represent the point B and to the applied force, we have:

Name

Beam

l

90 @ cm

f

50

ang

15

Now click in the icon Solve to get the answer:

Mr = -8.999 N*m ;  Fr = 0.000 N ;  angr = 208.262 degrees ;
Status = success.

As we expected the resultant is only a couple. Here the angle is irrelevant.