Test Question - Pulleys and Rubberbands

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Mgeiss
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I missed this question on the test and I don't get it...

I attached a scanned image of the question. If you can't make out the text it reads:

Two identical rubber bands connect masses A and B to a string over a frictionless pulley of negligible mass. The amount of stretch is greater in the band that connects to:
A
B
Both the same
 
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  • Scanned test question with printed text above answer choices A, B and Both the same, beside a diagram of a pulley hung from a ceiling with two rubber bands hanging masses A (higher) and B (lower).
    TestQuestion.jpg
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If the two rubber bands are identical, they must stretch the same amount for the same amount of force acting on them. If you have studied springs, that's a good way to look at the way the bands work. (F=kx, same k)
The next part to understanding this problem is considering how the free body diagram would look for each weight, specifically the tension on the bands. Note that the system is at equilibrium and consider the implications of that.
 
There's no reason to think that the system is in equilibrium. (Are the masses equal?)

Hint: How does the tension in the rubber bands relate to the tension in the string?