# Engineering Mechanics Couple system question

1. May 26, 2005

### Taiki_Kazuma

what is this problem searching for?

A 25-lb force acting in a vertical plane parallel to the yz plane is applied to the 8-in.-long horizontal handle AB of a socket wrench. Replace the force with an equivalent force-couple system at the origin O of the coordinate system.

See attached pic of the problem.

AO is 15-in.-long vertical

AB is 30 degrees off the x-axis

Force(in red) is 25-lb and is 20 degrees from the -z-axis

-------------------------------------------------------------

ok tell me if I"m wrong.

I think this problem is looking for the force that should be applied to cancel the other force but still have the same moment about O.

Please tell me if I'm thinking correctly...

however, how should I go about doing that? if that is the solution to this problem.

#### Attached Files:

• ###### Image003.jpg
File size:
24.4 KB
Views:
167
Last edited: May 26, 2005
2. May 27, 2005

### FredGarvin

Not exactly. What you need to do is come up with a force and moment that, when applied at the point O, are equivilent to the lone force acting at the end of the handle.

3. May 27, 2005

### Taiki_Kazuma

ok, I think I get it.....please correct me if I'm wrong (and let me know if I'm right)...

First I add vectors that are equal to F and -F at point O.

then I find the couple produced by F (original force) and -F. That will give me the answer of the couple moment at point O. and then I have F applied at O left over.

Is that what it is looking for?