# Vector Forces Problem

1. Sep 3, 2009

### ur5pointos2sl

The question states:
Use the measured angles to resolve each of the forces exerted by the strings into a z-component(Fz) and a horizontal component(FH).

Fz = F cos Theta
FH = F cos Theta

Given angles and forces:

30 deg. 270 N
135 deg. 170 N
240 deg. 260 N

I am a little confused about the problem and what exactly its asking for.

I will just show you my attempt for 30 deg. and see if it is the correct approach.

angle 30 deg
force 270 N
Fz = F cos Theta = 135
FH = F cos Theta = 234

Is this what they mean by a Z component and horizontal?

2. Sep 3, 2009

### Jebus_Chris

Resolving a vector means splitting it up into it's components. What you have is correct except you have $$cos\Theta$$ in both of them. I assume you meant the two equations to be
$$F_z = Fsin\theta$$
$$F_x = Fcos\theta$$
You got the right answers so I guess you just meant sin.

3. Sep 3, 2009

### ur5pointos2sl

Ok thank you. Now that I have done this there is a second part to the question.

Resolve FH into x- and y- components, Fx and Fy.

Fx=FH cos Phi
Fy=FH sin Phi

How would I use the equations since its Phi instead of Theta. This is a 3-D problem just to make you aware. Therefore, Phi is the angle between FH and the x axis. I am not sure how to get Phi.