# Homework Help: Tension in 3 cords

1. Oct 21, 2009

### dbakg00

This is my first post...is there a way to add a picture from my own computer to a post?

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

similiar to this problem but with different numbers

In my problem, C=T3, B=T2, and A=T1. The angle on the left is 30 and the one on the right is 45

2. Relevant equations

$$\vec{F}_{net} = \Sigma \vec{F} = m \vec{a}$$

3. The attempt at a solution

What I know...
1. T_c=w
2. T_a sin 30 + T_b sin 45 = w
3. T_a cos 30 - T_b cos 45 = 0
4. sin 45 = cos 45

T_a sin 30 + T_b sin 45 = w
T_a sin 30 + T_b cos 45 = w
becuse of # 3 above, I get
T_a sin 30 + T_a cos 30 = w
T_a(sin 30 + cos 30) = w
T_a(1.366) = w

...I'm stuck here. Please help direct me to find T_a in terms of W. As shown above I came up with "T_a=w/1.366" but the book came up with "T_a=.732w" Thanks is advance for the help.

Last edited: Oct 21, 2009
2. Oct 21, 2009

### tiny-tim

Welcome to PF!

Hi dbakg00! Welcome to PF!

(try using the X2 tag just above the Reply box )
erm … they're the same!

3. Oct 21, 2009

### willem2

w/1.366 is the same as 0.732w, so it is both correct

4. Oct 21, 2009

### dbakg00

I'm not seeing how those two are the same, would someone mind clarifying for me?

5. Oct 21, 2009

### tiny-tim

w/1.366 = w (1/1.366) = w(.732)

6. Oct 21, 2009

### dbakg00

thank you...i've been staring at this problem for so long, even the obvious becomes oblivious to me!