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Tension practice problem 
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#1
Aug511, 07:34 PM

P: 57

I'm trying to improve on tension problems so I am practicing using this website: http://www.education.com/studyhelp/article/tension/
I am on problem 6, but I keep coming up with the wrong answers. I attempted this by trying to show the net forces for each box. Box M net forces T upwards Mg downwards F = T  Mg = Ma Box 2M net forces T upwards T' downwards ***should I include the weight (2Mg) of this box??? Box 4M net forces 4Mg downwards T' upwards F = 4Mg  T' = 4Ma I have a feeling there is an error in box 2M that is fudging with my results. Lastly, does T = 6Mg? Help?? 


#2
Aug511, 07:46 PM

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#3
Aug511, 07:52 PM

P: 57

was my error that I didn't include the weight? or is it another entirely separate error in block 2m?



#4
Aug511, 07:54 PM

P: 57

Tension practice problem
Is the equation for block 2m:
F = 2Mg + T'  T = 2Ma? 


#5
Aug511, 08:12 PM

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#6
Aug511, 08:27 PM

P: 57

I solved it and it still incorrect.
Block M T  mg = ma <plug in m = 1 Kg T  9.8 = a T = 9.8 + a equation 1 Block 2M T' + 2mg  T = 2ma <Plug in m = 1 kg T' + 2(9.8)  T = 2a T' + 19.6  T = 2a equation 2 Block 4M 4mg  T' = 4ma <  plug in m = 1 kg 4(9.8)  T' = 4a T' = 39.2  4a equation 3 Substitute equation 1 and equation 3 into equation 2 equation 2: T' + 19.6  T = 2a (39.2  4a) + 19.6  (9.8 + a) = 2a Solve for a. a = 7 m/s^2 Correction answer is 8.6 m/s^2. 


#7
Aug511, 08:43 PM

P: 57

We were correct :D
The answer provided is incorrect I believe. Someone solved it out and got the same answer as I did here, http://www.myteacherpages.com/webpag...0SOLUTIONS.pdf. 


#8
Aug511, 08:44 PM

P: 57

Thank you phanthomjay *air hug*



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