# Homework Help: Accelerating elevator

1. Sep 25, 2006

### starfish794

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.

2. Sep 25, 2006

### Astronuc

Staff Emeritus
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?