# Resultant Force equation help

1. Nov 10, 2007

### navarro714

What type of equation would I use to find the resultant force?

Do I just add the vectors together? Or change them to X and Y variable?

2. Nov 10, 2007

### catkin

You could resolve each vector into x and y components, add the components and "unresolve" the 2 components back into a vector.

3. Nov 10, 2007

### PhanthomJay

You can't just algebraically add them, since in general they have different directions. Split each vector into its x and y components, then add the x components together to get Rx, and add the y components together to get Ry, and use pythagorus to get the magnitude of the resultant force (R = sq. rt. of (Rx^2 + Ry^2)), and use trig to get the direction of the resultant force (Ry/Rx=tan theta.)

4. Nov 10, 2007

### Vidatu

If they are collinear you can just add them, as long as you take sign into account. Otherwise, it is best to resolve them into x,y,and z components.

5. Nov 10, 2007

### navarro714

Thank you!!!! I've been looking through my text book for an hour!!!! I remeber my teacher telling me about that.