Tension in the strings (with diagram)

AI Thread Summary
The discussion focuses on calculating the tension in two strings based on a provided diagram. The equilibrium equations for vertical and horizontal forces are established, leading to expressions for T1 and T2. The calculations yield T2 as 259.8 N and T1 as 150 N. A correction is noted regarding the sign in the horizontal force equation, indicating that one component should be negative. The final tensions are confirmed as T1 = 150 N and T2 = 259.8 N, with an emphasis on the importance of proper sign usage in the equations.
AlphaRock
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Homework Statement


Find the tension in each string given the diagram.

Homework Equations



Fx = ma.
Fy = ma.

The Attempt at a Solution



Fy = 0. Because it's at equilibrium.
T1(sin30) + T2(sin60) - mg = 0.
T1 = [mg - T2(sin60)]/(sin30)

Fx = 0.
T1(cos30) + T2(cos60) = 0.
T1 = [-T2(cos60)]/(cos30)

T1 = T1
[mg - T2(sin60)]/(sin30) = [-T2(cos60)]/(cos30)
150/(sin30) = -T2[(cos60)/(cos30)] + T2[(sin60)/(sin30)]
150/(sin30) = T2[[(sin60)/(sin30)] - [(cos60)/(cos30)]]
T2 = 259.8 N

Substitute T2 into
T1 = [-T2(cos60)]/(cos30)
T1 = 150 N.

Therefore,
T1 = 150 N.
T2 = 259.8 N
Is this the right answer?
 

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AlphaRock said:
T1(cos30) + T2(cos60) = 0.
You need a minus sign here. One component is positive and the other is negative.
 
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