What is the coefficient of friction in this inclined plane problem?

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The discussion revolves around calculating the coefficient of friction for a system involving two masses on an inclined plane. The problem states that mass m2 (5 kg) is blocked and experiences a tension of T=10 N when stationary, but moves freely when released. The calculated coefficient of friction is initially confused, with one participant suggesting a value of 0.34, while the final answers provided are mu=0.2 and T=11 N when the system is in motion. The confusion arises from understanding the forces acting on m2, particularly the role of friction in maintaining equilibrium before movement. Ultimately, the problem is resolved with the correct calculations and understanding of the forces involved.
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Homework Statement


Two bodies with mass m1 and m2 are tied together with an inexstensible and massless string rolled over a massless pulley put at the top of the incline with angle 30 . m2=5 kg which is on the incline is blocked and T=10 N . m2 is let loose and the system starts moving freely. The distance traveled in the first second is d=0.5 m . Calculate: coefficient of friction , T when the system is moving .
The answers given are : mu=0.2 and T=11 N. [/B]

Homework Equations



The Attempt at a Solution


So I find a=1 m/s
But what confuses me is the given T=10 N when the system is not moving.
m2gsinθ =5*10*0.5=25 N
So there is another force acting in the direction of T so that the system is not moving. Is that force the force of friction ?
Or how can I calculate the coefficient of friction?
I am confused.
What I get for mu is 0.34 .
 
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##T_i=10\,N## and ##a_i=0## when system not move.
When system rolling, ##a_1=a_2##
Now you can see the forces to ##m_2##.
 
I've solved it . Thank you !
 
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