Why Is the Tension Different in Each Rope of an Accelerating Elevator?

AI Thread Summary
In an accelerating elevator, the tension in the ropes differs due to the forces acting on each block. The lower block's rope only needs to support its weight, while the upper block's rope must support the weight of both blocks. The tension in the lower rope is calculated as m2*g, while the tension in the upper rope is (m1 + m2)*(g + a), where 'a' is the elevator's acceleration. This results in different tension values for each rope, reflecting the additional force required to accelerate the upper block. Understanding these dynamics is crucial for solving problems involving tension in non-static systems.
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Two blocks are fastened to the ceiling of an elevator. The elevator accelerates upward at 1.70 m/s2. The blocks both have a mass of 11.5 kg. Find the tension in each rope.


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I'm stuck. It seems like the tension on both ropes should be the same but its not.
 
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Think of what the problem would be without the elevator stopped.

There are two blocks of mass m1 (upper mass) and m2 (lower mass). The bottom rope supports the weight of m2, which is m2*g. The top (upper) rope supports weights of both blocks m1* g + m2 * g = (m1+m2)*g.

Now what must one do to adjust the acceleration g if elevator is accelerating upward at 1.7 m/s2?
 

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