A lift of mass ′ m ′ is connected to a rope which is moving upward with the maximum acceleration ′ a ′ . For maximum safe stress, the elastic limit of the rope is ′ T ′ . The minimum diameter of the rope is ( g = gravitational acceleration):

Home » A lift of mass ′ m ′ is connected to a rope which is moving upward with the maximum acceleration ′ a ′ . For maximum safe stress, the elastic limit of the rope is ′ T ′ . The minimum diameter of the rope is ( g = gravitational acceleration):

Physics | Physics

A lift of mass ′ m ′ is connected to a rope which is moving upward with the maximum acceleration ′ a ′ . For maximum safe stress, the elastic limit of the rope is ′ T ′ . The minimum diameter of the rope is ( g = gravitational acceleration):

Solution: The correct answer is B.

$Let\text{ }the\text{ }tension\text{ }be\text{ }F.\,So,$

$F-mg=ma\to F=m(g+a)$

$Now,\,~T=\frac{F}{\pi {{r}^{2}}}$

$r={{\left( \frac{m\left( g+a \right)}{\pi T} \right)}^{1/2}}$

$D=2r$

$D=2{{\left( \frac{m\left( g+a \right)}{\pi T} \right)}^{\frac{1}{2}}}$

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