# Tension practice problem

by bulbasaur88
Tags: newton's second law, tension
 P: 57 I'm trying to improve on tension problems so I am practicing using this website: http://www.education.com/study-help/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??
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P: 6,049
 Quote by bulbasaur88 I'm trying to improve on tension problems so I am practicing using this website: http://www.education.com/study-help/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
yes
 Box 2M net forces T upwards T' downwards ***should I include the weight (2Mg) of this box???
always include the weight in any free body diagram
 Box 4M net forces 4Mg downwards T' upwards F = 4Mg - T' = 4Ma
yes
 I have a feeling there is an error in box 2M that is fudging with my results. Lastly, does T = 6Mg? Help??
yes, correct your error for the net forces acting in the FBD of the 2M block.
 P: 57 was my error that I didn't include the weight? or is it another entirely separate error in block 2m?
 P: 57 Tension practice problem Is the equation for block 2m: F = 2Mg + T' - T = 2Ma?