Finding Tensions (3 strings and 1 mass)

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The discussion focuses on calculating the tensions in three strings connected to a mass, with string 3 identified as having a tension of 200N. Participants suggest using a free-body diagram to analyze forces at the junction, emphasizing the need to account for both x and y components due to the lack of acceleration. Naming the tensions as T1 and T2 is recommended to simplify the equations. Additionally, drawing a vector triangle is proposed as an alternative method for solving the problem. The conversation aims to guide the original poster towards the correct approach for determining the tensions in the strings.
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Homework Statement



In the picture, what are the tensions in strings 1, 2, and 3?

http://www.flickr.com/photos/90172232@N04/8194075362/

Homework Equations





The Attempt at a Solution



I know string 3 is obviously 200N. I forget how to solve for the other strings. Do I add vectors here? string 1 = ?*sin(70) perhaps. Can somebody just point me in the right direction with this?
 
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At the junction, you have some forces acting. There is no acceleration. Draw a free-body diagram for the junction and write out equations representing the lack of acceleration.
 
Welcome to PF!

Hi Prima! Welcome to PF! :smile:

Start by giving things names …

call the tensions T1 and T2.​

Then write the equations for components in the x and y directions. :wink:

(alternatively, draw a vector triangle)
 

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