# Couple (forces)

1. Nov 4, 2007

### kring_c14

I need some help with number 4.16? well actually I just can't understand the question.. what I did is calculate all the moments with respect to A.. but I don't know if this has some relevance to the problem.. $$\sum MA= -2 (18.49) - .8 (4.5) +.8 (5.51)$$
I took the counter clockwise direction as negative... I don't have any idea what the hell Im doing....I really appreciate some help...

lots of thanks!!!!

2. Nov 4, 2007

### kring_c14

as for number 4.12---this is what I did... I'm really not sure if this is what the problem asks..
is this wrong???

3. Nov 4, 2007

heeeelp!!!

4. Nov 4, 2007

### kring_c14

the answer in 4.16 is supposed to 38.4... .

5. Nov 4, 2007

### PhanthomJay

Yes, you did pretty well...except on your last term for the positive moment you used 5.51 inches but you should have used the perpendicular distance fron the center of mass of that arm to the pivot, which is half that value.