Solving a Mass-Pulley System: m1 & m2

[shell4987]

Homework Statement

A block of mass m1 = 6.75 kg on a frictionless plane inclined at angle = 30.3° is connected by a cord over a massless, frictionless pulley to a second block of mass m2 = 2.07 kg hanging vertically (Fig. 5-54). (a) What is the acceleration of the hanging block (choose the positive direction up)? (b) What is the tension in the cord?

Homework Equations

Fynet= T-m2g= m2a aka T=m2g+m2a
Fxnet=m1g(sin)-T=m1a

when these two are put together it is, a=(m1g sin - m2g)/(m1+m2)

The Attempt at a Solution

So I used the equations above and first found acceleration to be -1.914m/s squared and then I used the acceleration and plugged it back into the problem to find T and I got it to be 16.32 N, these answers are wrong and I don't know what I did wrong. Can someone help me please?

 

[tabchouri]

Homework Equations

Fxnet=m1g(sin)-T=m1a

Can you tell where the (sin) came from ?

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Correct me if I am wrong.
http://ghazi.bousselmi.googlepages.com/présentation2

 

[shell4987]

Can you tell where the (sin) came from ?

From the free body diagram... when you extend out the normal force and make a triangle with the force of gravity, the sin is to find the x-component of the triangle

 

[tabchouri]

From the free body diagram... when you extend out the normal force and make a triangle with the force of gravity, the sin is to find the x-component of the triangle

the normal force counter acts only the gravity ?

-----------------------------------------------------
Correct me if I am wrong.
http://ghazi.bousselmi.googlepages.com/présentation2