Two blocks tied with massless rope sliding down an incline

AI Thread Summary
Two blocks are sliding down a 20-degree incline, with masses of 2.0 kg and 3.0 kg, and different coefficients of kinetic friction. The user calculated the net forces for each block but initially arrived at an incorrect tension of 2.94 N. After reevaluating the situation and realizing the importance of accurately drawing the Free Body Diagram, the user acknowledged that the error stemmed from not properly accounting for friction. The discussion highlights the significance of visualizing forces in physics problems to achieve correct solutions. Ultimately, the correct approach to the problem emphasizes the need for precise diagrams and calculations.
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Homework Statement


On 20 degree incline, there are two blocks tied together with a rope, sliding down. the block on the top has mass of 2.0 kg (m1) and u_k1(coefficient of kinetic friction for block 1) = .30 the block on the bottom of the incline has mass of 3.0 kg (m2) and u_k2 = .20
What is the tension of the rope?


Homework Equations


F=ma, f = F_N*u


The Attempt at a Solution


I found F_net for each block by F_net = F_gx(Force of gravity in horiz. direction) - f(friction)
and got F1_net = .8236 N and F2_net = 4.1754 N
and because of acceleration constraint, and because block 1 has slower accel, I found accel for block 1, which was .4118 m/s^2 and found F = m2(a) = 1.2354 N
Because F2_net is larger than F = m2(a), I subtracted those two and got T = 2.94 N which is not correct.
 
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Draw a Free Body Diagram for each block.

How did you account for friction?
 
I figured it out! I just didn't draw the right free body diagram..

Thanks!
 
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