Multiple Pulleys and Masses with Friction

AI Thread Summary
The discussion focuses on solving a physics problem involving multiple pulleys, masses, and friction. The user has calculated the tensions T1 and T2, as well as the accelerations a1 and a2, using equations derived from Newton's second law. The final results indicate T1 is 113.68N, T2 is 196N, a1 is 2.548 m/s², and a2 is 1.274 m/s². The user seeks validation of their solution and invites feedback on any potential errors or improvements. Overall, the thread emphasizes the importance of checking calculations in physics problems involving complex systems.
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Multiple Pulleys and Masses with Friction (Picture Included)

Homework Statement


http://content.screencast.com/users/Waraa/folders/Snagit/media/2d699ba1-32e0-4d9c-b79f-1a1d85dccd12/03.19.2012-15.49.46.png

I have solved the question but I am still iffy as to whether my solution is correct or not.

Homework Equations


Let m1 = 10kg.
Let m2 = 20kg.

(1) m1a1 = T1 - μm1g
(2) m2aa = m2g - T2
(3) 2T1 = T2
(4) 2a2 = a1


The Attempt at a Solution


T2 = m2g
T2 = (20kg)(9.8m/s2)
T2 = 196N

T1 = \frac{T_{2} + μm_{1}g}{2}
T1 = \frac{196N + (0.32)(10kg)(9.8m/s^{2})}{2}
T1 = 113.68N

Sub (3) and (4) into (2)
m2a2 = m2g - T2
m2(\frac{a_{1}}{2}) = m2g - 2T1

Called this new equation (5).
(5) m2(\frac{a_{1}}{2}) = m2g - 2T1


(1) m1a1 = T1 - μm1g
(5) m2(\frac{a_{1}}{2}) = m2g - 2T1

(1) + (5)
m1a1 + m2(\frac{a_{1}}{2}) = T1 - μm1g + m2g - 2T1
a1(m1 + m2(\frac{1}{2}) = -μm1g + m2g - T1
a1(10kg + 20kg(\frac{1}{2}) = -(0.32)(10kg)(9.8m/s2)+(20kg)(9.8m/s2)-113.68N
a1 = 2.5448 m/s2

from (4)
2a2 = a1
a2 = \frac{a_{1}}{2}
a2 = \frac{2.548m/s^{2}}{2}
a2 = 1.274 m/s2

Therefore, T1 = 113.68N, T2 = 196N, a1 = 2.548 m/s2, and a2 = 1.274 m/s2.

My question is if my solution is correct. Please check and reply back with suggestions or corrections. Thank you so much.
 
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