# Component vector method for resultant force

1. Mar 24, 2011

### argentnox

1. The problem statement, all variables and given/known data

An object has two ropes attached. One is on the x axis (positive) with a 60 lb force. One is 120* (Quadrant II) from the first rope with a 30 lb force. I have to find the resultant force and angle using the component vector method of addition NOT the parallelogram method.

2. Relevant equations

Fa + Fb = R

3. The attempt at a solution

I set up a table of components, but I am not sure if they are correct. I am just really confused as to how to approach this problem. I know how to do it using the parallelogram method, but it seems like some important piece of information is missing for doing it using the component vector method.

A=30 lb
B= 60 lb

Angle A=120*
Angle B=0*

Ax = ??
Bx = 60 lb

Ay = ??
By = 0

Last edited: Mar 24, 2011
2. Mar 25, 2011

### tiny-tim

welcome to pf!

hi argentnox! welcome to pf!

(try using the X2 icon just above the Reply box )

to find the component in a direction, always multiply by cos of the angle to that direction

3. Mar 25, 2011

### argentnox

Thank you, I will try that and see how I do. If it is okay, I will probably come back to make sure I got the correct answer. I figure if I got the answer correct, I must have done the work correctly. ;)