# Homework Help: Moment of force

1. Dec 24, 2015

### Saanchi

1. The problem statement, all variables and given/known data
Calculate resultant moment of forces about pt O and state its direction.

2. Relevant equations
Put the picture. Check it out

3. The attempt at a solution
What I did was :
B: 40 Nm
C : 120Nm.

I'm not sure to add or subtract for resultant. What I did::
Add. A-B as they are in same direction : 60➕40 : 100
Then subtract 120 to it as opposite direction direction

Therfore. 20 Nm

Am I right about the resultant or totally wrong?

Direction : Clockwise.

#### Attached Files:

• ###### WP_20151224_002.jpg
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2. Dec 24, 2015

### FactChecker

You are correct. You should specify that it is clockwise around the axis coming out of the page. In complicated situations, you define a right-hand coordinate system. Then your moments around an axis have the appropriate sign and you don't have trouble keeping track of clockwise, counterclockwise around which axis.

Last edited: Dec 24, 2015
3. Dec 24, 2015

### Saanchi

Alright. Thanks :)