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Homework Statement
Hello! I have a question about the following problem:
Two point masses m1 and m2 are attached to isolating wires to point P. They are both positively charges (charge Q1 and Q2) and in the picture you can see the situation at equilibrium.
What is the proportion of the masses (m1 / m2)?[/B]
Homework Equations
The Attempt at a Solution
So this is how I would do it:
We have the weight force for m_{1} which is W_{1} = m_{1} * g and for m_{2} we have W_{2} = m_{2} * g
The forces W are is in ydirection
For other forces of the ydirection we have to break down the tension force into its x and y components.
For m_{1} we can say that the tension force in y direction is T_{1y} = T_{1} * cos (60°) and for m_{2} the tension force in y direction is T_{2y} = T_{2} * cos(30°)
this means that T_{1} * cos (60°)  m_{1} * g = 0
and T_{2} * cos (30°)  m_{2} g )= 0
or T_{1} * cos (60°) = m_{1} * g
and T_{2} * cos (30°) = m_{2} * g
If we devide the both equations we get
T1 / T2 * cos(60°) / cos(30°) = m1 / m2
for cos(60) = 1/2
for cos (30) = sqrt (3) /2
cos(60)/cos(30) = 1/sqrt(3)
which leads us to T1 / T2 * 1/sqrt(3) = m1/m2
how can I get rid of T1/T2 and what is m1/m2?
Thanks for your help!
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