Elevator Forces: Fupward vs Fnet vs a

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    Elevator Forces
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The discussion centers on understanding the forces acting on an elevator, particularly the relationship between upward force, net force, and acceleration. The maximum acceleration of 0.068g raises questions about how an elevator can ascend when its acceleration is less than gravitational force. It is clarified that the upward force must exceed the weight of the elevator for it to ascend, regardless of the net force being smaller than the weight. The confusion lies in differentiating between net force, upward force, and acceleration in determining the elevator's ability to lift. Ultimately, the upward force is crucial for lifting the elevator, even if the net force appears smaller than the weight.
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For elevator problem in Force, I have some confusions about basic concepts. Here give an example: an elevator is to be designed so that the maximum acceleration is 0.068g. Here why would the elevator's acceleration smaller than the gravity, then can it still pull the whole elevator up? Or whether it can pull elevator up depends on the upward force not acceleration? Fnet=Fupward-Fg(weight), Is a=0.068g here net acceleration? Fnet=0.068g*m? I think Fupward must be larger than the weight, but then the net force is smaller than the weight, does it matter? I mean if the net force is smaller than the weight, will the tension still be able to pull/lift the elevator up? Or we only look at Fupward to determine if it can lift the elevator. My confusions here are: a and Fnet vs Fupward.
THanks.
 
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The force is controlled so that the maximum acceleration of the elevator and it's load are .068g.
 
Jeff Reid said:
The force is controlled so that the maximum acceleration of the elevator and it's load are .068g.

sry, I don't quite understand what do you mean by the force is controlled?
 

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