An Atwood machine consists of masses 2m and m and is suspended inside a lift descending with acceleration a. As a → g, the tension in the string approaches:
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An Atwood machine consists of masses 2m and m and is suspended inside a lift descending with acceleration a. As a → g, the tension in the string approaches:

G1 Physics · Accepted Answer

In the lift frame, gₑff = g-a. For masses 2m and m, tension is T = 2(2m)(m)gₑff/(3m) = (4/3)m(g-a). As a → g, g-a → 0, therefore T → 0.