Understanding the Forces of a Moving Lift: T and T1

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The discussion focuses on calculating the tensions T and T1 in a lift system under different conditions. When the lift is stationary, T1 is determined to be 3mg and T is 2mg. For a lift moving with acceleration a, the new tensions are T1 = 3m(g+a) and T = 2m(g+a). Participants emphasize the importance of drawing separate free body diagrams for each mass and correctly assigning signs to the acceleration. Overall, the calculations and reasoning presented are affirmed as correct.
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This is my problem,
uploadfromtaptalk1373171905114.jpg

ABCD is a lift.

1-- when the lift not moving i want the T and T1.
T1= 3mg
T= 2mg
Right ?

2-- when the lift is moving with accelartion a. I want to know the new T and T1.
Are they
T1 = 3m(g+a)
T = 2m(g+a)

Am i doing it right?
 
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Please show your reasoning.
Are the masses not equal then? I don't see that on your diagram.
You should draw separate free body diagrams for each mass.
 
First mass is m
Second one is 2m
 
That looks right. Just make sure you assign the correct +/- sign to 'a'.
 
NascentOxygen said:
That looks right. Just make sure you assign the correct +/- sign to 'a'.

Yeah, thank you sir
 
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