What Is Her Apparent Weight in a Decelerating Elevator?

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shimizua
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Homework Statement


Referring to the problem above, if the elevator's descending speed is measured at 10 m/s at a given point, but its speed is decreasing by 2.5 m/s2, what is her apparent weight?.
And the problem above it was this
A 58.0 kg girl weighs herself by standing on a scale in an elevator. What is her apparent weight when the elevator is descending at a constant speed of 10 m/s?


Homework Equations


So i was able to find the answer to the first question which was 568N and found it by doing her mass times the gravity. but i have no i idea of how to do it when the speed it decreasing.


The Attempt at a Solution


i tried doing her mass times her acceleration which was 10m/s and that was wrong and so i then tried doing her mass time her deceleration of 2.5m/s/s and that was wrong as well. if you could just help with an equation that should be good enough. thanks
 
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Her apparent weight will be the weight due to gravity plus the force exerted on her by the lift.
 
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ok so i would use my initial number of 568N and add that to what? her mass times the deceleration?
cool so i put that in and it does work, thanks man
 
Yes, force = mass times acceleration. If the elevator is accelerating upward, then you would feel g+ mass * acceleration. If the elevator is accelerating downward, then you would feel g- mass*acceleration.