Solving Tension in 3 Cords: Find T_a in Terms of W

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The discussion focuses on solving for T_a in a physics problem involving tensions in cords at angles of 30 and 45 degrees. The user initially derived T_a as w/1.366 but was confused when the textbook provided T_a as 0.732w. A participant clarified that both expressions are equivalent, as w/1.366 simplifies to 0.732w. The conversation highlights the importance of understanding algebraic manipulation in physics problems. The user expresses gratitude for the clarification, indicating a collaborative learning environment.
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This is my first post...is there a way to add a picture from my own computer to a post?

Homework Statement



similiar to this problem but with different numbers
P5.26a.gif

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



Homework Equations



<br /> \vec{F}_{net} = \Sigma \vec{F} = m \vec{a}<br />





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.
 
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Welcome to PF!

Hi dbakg00! Welcome to PF! :smile:

(try using the X2 tag just above the Reply box :wink:)
dbakg00 said:
… I came up with "T_a=w/1.366" but the book came up with "T_a=.732w"

erm :redface: … they're the same! :smile:
 
w/1.366 is the same as 0.732w, so it is both correct
 
I'm not seeing how those two are the same, would someone mind clarifying for me?
 
w/1.366 = w (1/1.366) = w(.732) :wink:
 
thank you...i've been staring at this problem for so long, even the obvious becomes oblivious to me!
 
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