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## Homework Statement

In the figure

Find the magnitude of the acceleration of the masses and the tension of the cord

## Homework Equations

(1) [tex]\sum Fnet = ma[/tex]

(2) [tex]f_k = \mu_k*F_n[/tex]

## The Attempt at a Solution

I applied (1) to the first block in the x-direction and then in the y-direction

Found:

[tex]F_n - m_1*g*\sin\theta = 0 (a_y = 0) => F_n = m_1*g*\sin\theta[/tex] [a]

[tex]T - f_k - m_1*g*\cos\theta = m_1*a_x[/tex]

I applied (1) to block 2

[tex]m_2*g - T = m_2*a_y [/tex]

Added [a] to

Added [a] to

[tex]m_2*g - f_k - m_1*g*\cos\theta = m_1*a_x + m_2*a_y[/tex]

<=>[tex]m_2*g - \mu_k *m_1*g*\sin\theta - m_1*g*\cos\theta = (m_1+m_2)a[/tex]

<=>[tex]g*\frac{m_2 - \mu_k *m_1*\sin\theta - m_1*\cos\theta}{m_1+m_2}=a[/tex]

What am I doing wrong?[tex]m_2*g - f_k - m_1*g*\cos\theta = m_1*a_x + m_2*a_y[/tex]

<=>[tex]m_2*g - \mu_k *m_1*g*\sin\theta - m_1*g*\cos\theta = (m_1+m_2)a[/tex]

<=>[tex]g*\frac{m_2 - \mu_k *m_1*\sin\theta - m_1*\cos\theta}{m_1+m_2}=a[/tex]

What am I doing wrong?